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Brownlie's Principles of Public International Law, 8th Edition by Crawford, James R (27th September 2012) [OLD EDITION]

Part VI International Transactions, 16 The Law of Treaties

From: Brownlie's Principles of Public International Law (8th Edition)

James R Crawford

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Vienna Convention on the Law of Treaties — Pacta sunt servanda — Object & purpose (treaty interpretation and)

(p. 367) 16  The Law of Treaties

1.  Introduction1

Many international disputes are concerned with the interpretation and effects of international agreements, that is, treaties, and much of the practical content of state relations is embodied in and structured by treaties. International organizations, including the United Nations, have their legal basis in multilateral treaties. So too do arrangements on matters ranging from geostationary orbit to the regulation of intellectual property to the governance of Antarctica. Networks of bilateral treaties regulate such matters as aviation, boundaries, extradition, investment protection, and shared natural resources.

Since 1949 the ILC has concerned itself with the law of treaties.2 In 1966 it adopted a set of 75 draft articles:3 these formed the basis for the 1969 Vienna Convention on the Law of Treaties (VCLT), which entered into force on 27 January 1980.4

At the time of its adoption, it could not have been said that the VCLT was, taken as a whole, declaratory of general international law. Various provisions clearly involved progressive development. Nonetheless it has had a very strong influence, and a good number of articles are now essentially declaratory of existing law; those which are not (p. 368) constitute presumptive evidence of emergent rules.5 Indeed its provisions are regarded as the primary source of the law, irrespective of whether the VCLT applies qua treaty in the given case.6 In Namibia the Court observed that:

The rules laid down by the Vienna Convention…concerning termination of a treaty relationship on account of breach (adopted without a dissenting vote) may in many respects be considered as a codification of existing customary law on the subject.7

The European Court of Justice has observed that the customary international law of treaties forms part of the European legal order, and it generally follows the VCLT (implicitly or explicitly);8 the WTO dispute settlement body has also emphasized the customary status of the VCLT rules of treaty interpretation.9

The Convention was adopted by a very substantial majority at the Vienna Conference10 and covers the main areas of the law of treaties. It does not deal with (a) treaties between states and organizations, or between two or more organizations;11 (b) state succession to treaties;12 or (c) the effect of armed conflict on treaties,13 each of which has been the subject of separate ILC projects.

(p. 369) (A)  Definition of ‘Treaty’

A provisional ILC draft defined a ‘treaty’ as:

any international agreement in written form, whether embodied in a single instrument or in two or more related instruments and whatever its particular designation (treaty, convention, protocol, covenant, charter, statute, act, declaration, concordat, exchange of notes, agreed minute, memorandum of agreement, modus vivendi or any other appellation), concluded between two or more States or other subjects of international law and governed by international law.14

The reference to ‘other subjects’ of the law was designed to provide for treaties concluded by international organizations, the Holy See, and other international entities. But the ILC’s Final Draft, and the VCLT itself, are confined to treaties between states (Article 1).15 Article 3 provides that the fact that the Convention is thus limited shall not affect the legal force of agreements between states and other subjects of international law or between such other subjects.

Article 2(1)(a) defines a treaty as ‘an international agreement concluded between States in written form and governed by international law, whether embodied in a single instrument or in two or more related instruments and whatever its particular designation’. The distinction between a transaction which is a definitive legal commitment between two states, and one which involves something less than that is difficult to draw. But the form or title of the instrument, for example, a joint communiqué, is not decisive.16

Article 2(1)(a) also stipulates that the agreements to which the Convention extends must be ‘governed by international law’; this excludes commercial arrangements made between governments under one or more national laws.17

(B)  The Functions of Treaties

McNair long ago pointed to the variety of functions which treaties perform.18 Some treaties, dispositive of territory and rights in relation to territory, are like conveyances. (p. 370) Treaties involving bargains between a few states are like contracts; whereas the multilateral treaty creating either a set of rules, such as the Hague Conventions on the Law of War, or an institution, such as the Copyright Union, is ‘law-making’. The treaty constituting an institution is akin to a charter of incorporation. It is certainly fruitful to contemplate the different features of different kinds of treaties and even to expect the development of specialized rules. Thus the effect of war between parties varies according to the type of treaty involved. However, McNair and others have tended to support the position that the genus of treaty produces fairly general effects on the applicable rules. Thus the lawmaking character of a treaty is said (a) to rule out recourse to preparatory work as an aid to interpretation; (b) to avoid recognition by one party of other parties as states or governments; and (c) to render the doctrine of rebus sic stantibus inapplicable.19

By contrast the ILC deliberately avoided any classification of treaties along broad lines and rejected the concept of the ‘objective regime’ in relation to the effects of treaties on non-parties. It accepted specialized rules in a few instances,20 but did not consider it necessary to make a distinction between ‘law-making’ and other treaties.21 The ILC and in turn the Vienna Conference saw the law of treaties as essentially a unity.22 Moreover jurists are now less willing to accept categorical distinctions between treaty-contract (vertrag) and treaty-law (vereinbarung).23 The contrast intended between the bilateral political bargain and the ‘legislative act’ produced by a broad international conference does not correspond to reality. Political issues and bargaining lie behind law-making efforts like UNCLOS III. Further, the distinction obscures the real differences between treaty-making and legislation in a municipal system. Nonetheless, it should be acknowledged that some of the VCLT rules, for example Article 18 and the rules relating to reservations, may work better with contractual-type agreements than with law-making ones.

(C)  Participation in Treaties

In an early draft the ILC defined a ‘general multilateral treaty’ as ‘a multilateral treaty which concerns general norms of international law and deals with matters of general interest to States as a whole’.24 But which states and other entities are permitted to participate in drawing up such a treaty is a matter for the proponents, or in the case of a treaty concluded under the auspices of an international organization, the organization. In the ILC it was proposed that states should have a right to become parties to this type of treaty, a solution adopted in the insubstantial form that the right existed except where the treaty or the rules of an international organization (p. 371) provided otherwise.25 The ILC’s Final Draft contained no provision on the subject and amendments intended to give ‘all States a right to participate in multilateral treaties’ were defeated at the Vienna Conference.26

2.  Conclusion of Treaties

(A)  Form and Intention27

How treaties are negotiated and brought into force depends on the intention of the parties. There are no overriding requirements of form:28 for example, an agreement recorded in an exchange of letters or even the minutes of a conference may have the same legal effect as a formally drafted treaty contained in a single instrument.29 In practice form is governed partly by usage, and will vary according to whether the agreement is expressed to be between states, heads of states, governments, or particular ministers or departments. The VCLT applies only to agreements ‘in written form’ but Article 3 stipulates that this limitation is without prejudice to the legal force of agreements ‘not in written form’.30

Where the parties wish to record mutual understandings for the conduct of their business or other relationships, but do not intend to create legally binding obligations, they often conclude non-binding instruments commonly referred to as memoranda of understanding (MOUs).31 The name of the instrument is not conclusive as to its legal status, however; what matters is the intention of the parties as reflected in the terms of the instrument.32

(B)  Full Powers and Signature33

The era of absolute monarchs and slow communications produced a practice whereby a state agent would be given full powers to negotiate and to bind his principal. In modern practice, full powers give the bearer authority to negotiate and to sign and seal (p. 372) a treaty but not to commit the state. In the case of less formal agreements full powers are often dispensed with.34 Thus the definition in VCLT Article 2(c):

…a document emanating from the competent authority of a State designating a person or persons to represent the State for negotiating, adopting or authenticating the text of a treaty, for expressing the consent of a State to be bound by a treaty, or for accomplishing any other act with respect to a treaty.

One example of full powers arose in Land and Maritime Boundary between Cameroon and Nigeria, with the Court confirming that the full powers afforded to a head of state derive from his or her position at the top of a state’s hierarchy.35 This position was expanded upon—beyond the law of treaties—in Genocide, with VCLT cited for the proposition that ‘every Head of State is presumed to be able to act on behalf of the State in its international relations’.36

The successful outcome of negotiation is the adoption and authentication of an agreed text. Signature has, as one of its functions, authentication, but a text may be authenticated in other ways, for example by incorporation in the final act of a conference or by initialling.37

Where the signature is subject to ratification, acceptance, or approval, signature does not establish consent to be bound nor does it create an obligation to ratify.38 What it does is to qualify the signatory to proceed to ratification, acceptance, or approval; it also creates an interim obligation of good faith to refrain from acts calculated to frustrate the objects of the treaty.39

Where the treaty is not subject to ratification, acceptance, or approval, signature establishes consent to be bound. Sometimes signature may be dispensed with: the text may be adopted or approved by resolution of the UN General Assembly and submitted to member states for accession.

(C)  Ratification

Ratification involves two distinct procedural acts: the first an internal act of approval (e.g. by the parliament, or the Crown in the UK); the second the international procedure (p. 373) which brings a treaty into force by a formal exchange or deposit of instruments of ratification. Ratification in the latter sense is an important act involving consent to be bound.40 But everything depends on the intention of the parties, and modern practice contains many examples of less formal agreements intended to be binding on signa-ture.41 As to the small number of treaties containing no express provision on ratification, the ILC initially considered that ratification should be required.42 However, it changed its view, partly because of the difficulty of applying the presumption to treaties in simplified form. VCLT Article 14 regulates the matter by reference to the parties’ intention without any presumption.

(D)  Accession, Acceptance, and Approval

‘Accession’ occurs when a state which did not sign a treaty formally accepts its provisions: this may be before or after the treaty has entered into force. The conditions for accession and the procedure involved depend on the provisions of the treaty. Accession may be the only means of becoming a party, as in the case of a convention approved by the General Assembly and proposed for accession by member states.43 Recent practice has introduced the terms ‘acceptance’ and ‘approval’ to describe the substance of accession. Terminology is not fixed, however, and where a treaty is expressed to be open to signature ‘subject to acceptance’, this is equivalent to ‘subject to ratification’.

(E)  Other Expressions of Consent to be Bound

These are not the only means by which consent to be bound may be expressed. Other means may be agreed, for example an exchange of instruments constituting a treaty.44

(F)  Entry into Force, Deposit, and Registration

The provisions of the treaty determine how and when the treaty enters into force. Where the treaty does not specify a date, there is a presumption that the treaty comes into force as soon as all the negotiating states have consented to be bound.45

After a treaty is concluded, the written instruments of ratification, accession, etc and also reservations and other declarations are placed in the custody of a depositary, (p. 374) which may be one or more states or an international organization.46 The UN Secretariat plays a significant role as depositary of multilateral treaties.

Article 102 of the UN Charter provides as follows:

  1. 1.  Every treaty and every international agreement entered into by any Member of the United Nations aft er the present Charter comes into force shall as soon as possible be registered with the Secretariat and published by it.

  2. 2.  No party to any such treaty or international agreement which has not been registered in accordance with the provisions of paragraph 1 of this Article may invoke that treaty or agreement before any organ of the United Nations.

This provision (which goes back to President Woodrow Wilson)47 is intended to discourage secret diplomacy and to promote the availability of treaty texts. The Secretariat accepts agreements for registration without conferring any status on them or the parties which they would not have otherwise. However, this is not the case where the regulations provide for ex officio registration. This involves initiative by the Secretariat and extends to agreements to which the UN is a party, trusteeship agreements, and multilateral agreements with the UN as depositary. The phrase ‘every international agreement’ has a wide scope. Technical intergovernmental agreements, declarations accepting the optional clause in the Statute of the International Court, agreements between organizations and states, agreements between organizations, and unilateral engagements of an international character are included.48

Non-registration does not affect the validity of agreements, but these may not be relied upon in proceedings before UN organs. In relation to the similar provision in the Covenant of the League the view was expressed that an unregistered agreement could be invoked if otherwise appropriately publicized.49

3.  Reservations50

VCLT Article 2(d) defines a reservation as ‘a unilateral statement, however phrased or named, made by a State, when signing, ratifying, accepting, approving or acceding to (p. 375) a treaty, whereby it purports to exclude or to modify the legal effect of certain provisions of the treaty in their application to that State’. It is to be distinguished from an interpretative declaration, which is an expression of view by a declarant state as to the meaning of a treaty which is not put forward as a condition of being bound.51

Considerable uncertainty has surrounded the law and practice with regard to reservations.

(A)  Historical Background

League of Nations practice in regard to multilateral conventions lacked consistency. The League Secretariat, and later the UN Secretary-General, as depositary of conventions concluded under the auspices of the League, followed the principle of absolute integrity: a reservation would only be valid if the treaty permitted it or all contracting parties accepted it; otherwise the reserving state would not be considered a party.52 In contrast the Pan-American Union, later the Organization of American States, adopted a flexible system which permitted a reserving state to become a party vis-à-vis non-objecting states. This system, dating from 1932, promotes universality at the expense of consistency of obligation.

Following the adoption of the Genocide Convention in 1948, a divergence of opinion arose on the admissibility of reservations to the Convention, which contained no provision on the subject; an advisory opinion was sought. The International Court stressed the divergence of practice and the special characteristics of the Convention, including the intention of the drafters that it be universal in scope. The Court’s principal finding was that ‘a State which has made…a reservation which has been objected to by one or more of the parties to the Convention but not by others, can be regarded as being a party to the Convention if the reservation is compatible with the object and purpose of the Convention’.53

In 1951 the ILC rejected the ‘compatibility’ criterion as too subjective, preferring a rule of unanimous consent.54 However, in 1952 the General Assembly requested the Secretary-General to conform practice to the opinion of the Court and, in respect of (p. 376) future conventions of which the Secretary-General was depositary, to leave it to each state to draw its own conclusions from reservations communicated to it.55 In 1959 the General Assembly extended this to cover all UN conventions, unless they contained contrary provisions.56 In 1962 the ILC decided in favour of the ‘compatibility’ rule.57

(B)  Impermissible Reservations

VCLT Article 20 provides for acceptance of and objection to reservations other than those expressly authorized by a treaty.58 The ‘compatibility’ test is by no means ideal;59 in particular its application is a matter of appreciation, left to individual states. How is the test to apply to provisions for dispute settlement, for example? In practical terms the ‘compatibility’ test may not sufficiently maintain the balance between the integrity and the effectiveness of multilateral conventions in terms of a firm level of obligation. It is very doubtful whether there can be any place for the ‘compatibility’ test in relation to unlawful reservations.60

The issue of severability in relation to human rights treaties has been particularly controversial.61 In Belilos62 and Loizidou63 the European Court of Human Rights treated the objectionable reservation as severable. So did the Human Rights Committee: a state could not, for example, reserve the right to subject persons to torture, or to presume a person guilty unless proven innocent;64 rather than the state’s participation in the treaty being negated, it was held to be a party to the treaty without benefit of its reservation, whatever its underlying intention may have been.

(C)  The ILC Guide (2011)

Some of the difficulties in respect of permissibility of reservations are addressed in the comprehensive Guide to Practice on Reservations to Treaties adopted by the (p. 377) ILC in 2011, the culmination of 15 years of work.65 The Guide is intended as a ‘toolbox’ for practitioners in dealing with the permissibility and effects of reservations, pointing them towards solutions consistent with existing rules. The Guide is not a binding instrument and is not intended to form the basis of a convention66 but it is likely to make a significant contribution to clarification of law and practice in this area.

On the question of severability the Guide adopts an ingenious intermediate solution. Under Guideline 4.5.1, an invalid or impermissible reservation is null and void, and has no legal effect. Practice has varied on whether the author of an invalid reservation remains bound by the treaty without the benefit of the reservation, or whether the nullity of the reservation vitiates that party’s consent to be bound altogether.67 The Guide provides a presumption that the former applies, unless the contrary intention of that party is expressed or otherwise established.68 In this way the Guide affirms that the key to the status of the reserving party in relation to the treaty is that party’s intention,69 and offers ‘a reasonable compromise between the underlying principle of treaty law—mutual consent—and the principle that reservations prohibited by the treaty or incompatible with the object and purpose of the treaty are null and void’.70

4.  Observance, Application, and Interpretation of Treaties

(A)  Pacta Sunt Servanda

The VCLT entails a certain presumption as to the validity and continuance in force of a treaty.71 This may be based upon pacta sunt servanda as a general principle of international law: a treaty in force is binding upon the parties and must be performed by them in good faith.72 Legally, treaties are enduring instruments, not easily disposed of.73 Internal law may not be invoked to justify a failure to perform a treaty.74

(p. 378) (B)  Application of Treaties

Treaties are not retroactive; that is, unless a contrary intention is established, parties are only bound in respect of acts or facts taking place after the treaty has entered into force for the party in question.75 Unless otherwise stated, they apply within the whole territory of the states parties.76

VCLT Article 30 covers the application of successive treaties to the same subject-matter.77 The relation of treaties between the same parties and with overlapping provisions is primarily a matter of interpretation, aided by presumptions. Thus it is to be presumed that a later treaty prevails over an earlier treaty concerning the same subject-matter. A treaty may provide expressly that it is to prevail over subsequent incompatible treaties; Article 103 of the UN Charter goes further by providing that in the case of conflict, obligations under the Charter prevail over obligations arising under any other international agreement. Article 351 of the Treaty on the Functioning of the European Union (TFEU) provides that pre-existing rights and obligations shall not be affected by its provisions or those of the Treaty on European Union (TEU), but that where incompatibilities exist, parties shall take appropriate steps to eliminate them.78 Whether or not there is a conflict in a given case is of course a matter of interpretation: thus a resolution which is capable of being performed in a manner consistent with the International Covenant on Civil and Political Rights, for example, may be construed as not intending to override the relevant rights.79 VCLT Article 59 provides for the termination or suspension of a treaty in certain circumstances where all parties have concluded a later treaty relating to the same subject-matter.

(C)  Interpretation of Treaties80

(i)  Competence to interpret

Obviously the parties have competence to interpret a treaty, but this is subject to the operation of other legal rules. The treaty itself may confer competence on an ad hoc (p. 379) tribunal or the International Court. The UN Charter is interpreted by its organs, which may seek advisory opinions from the Court.81

(ii)  The ‘rules of interpretation’

Various ‘rules’ for interpreting treaties have been put forward over the years.82 These include the textual approach, the restrictive approach, the teleological approach, and the effectiveness principle. Of these only the textual approach is recognized in VCLT: Article 31 emphasizes the intention of the parties as expressed in the text, as the best guide to their common intention.83 The jurisprudence of the International Court likewise supports the textual approach.84

In a number of cases the Permanent Court committed itself to the principle that provisions implying a limitation of state sovereignty should receive a restrictive inter-pretation.85 As a general principle of interpretation this is question-begging, and later decisions have given less scope to it.86 However, the principle may operate in cases concerning regulation of core territorial privileges. In these instances it is not an ‘aid to interpretation’ but an independent principle.

According to the teleological approach, any ambiguity in a treaty text should be resolved by preferring the interpretation which gives effect to the object and purpose of the treaty.87 This may involve a judicial implementation of purposes in a fashion not contemplated by the parties. The teleological approach has many pitfalls, not least its overt ‘legislative’ character.

A version of the teleological approach is often referred to under the rubric of ‘evolutive’ (or ‘progressive’) interpretation. It was apparently applied in Navigational Rights. There the question was whether the phrase ‘for the purposes of commerce’ in a boundary treaty of 1858 extended to cover commercial tourism, that is, the carriage (p. 380) of passengers for hire. The Court held that the term in the 1858 treaty should be interpreted so as to cover all modern forms of commerce, of which tourism is one:

[W]here the parties have used generic terms in a treaty, the parties necessarily having been aware that the meaning of the terms was likely to evolve over time, and where the treaty has been entered into for a very long period or is ‘of continuing duration’, the parties must be presumed, as a general rule, to have intended those terms to have an evolving meaning.88

The result was evidently correct; it was relevant that the right of transit was permanent in character, being part of the regime of the boundary. But the Court may have assumed that the term ‘commerce’ in the mid-nineteenth century had a stereotyped meaning; in fact, persons were carried for hire on the river at the time of the treaty.

As to the effectiveness principle, in advisory opinions and judgments concerning powers of UN organs, the Court has often adopted a principle of institutional effectiveness and has implied the existence of powers which in its view were necessary or conducive to the purposes of the Charter.89 The European Court of Human Rights has preferred an effective and ‘evolutionary’ approach in applying the European Convention on Human Rights.90 However, this approach suffers from the same defects as the principle of restrictive interpretation. The ILC did not adopt the principle, considering that, as a matter of existing law it was reflected sufficiently in the doctrine of interpretation in good faith in accordance with the ordinary meaning of the text.91

Care must be taken to ensure that such ‘rules’ do not become rigid and unwieldy instruments that might force a preliminary choice of meaning rather than acting as a flexible guide. The ILC avoided taking a doctrinaire position and instead confined itself to isolating ‘the comparatively few general principles which appear to constitute general rules for the interpretation of treaties’.92 Those principles appear as an economical code in VCLT Articles 31 and 32, following exactly the ILC’s Final Draft .

(iii)  The general rule: VCLT Article 31

VCLT Article 31, entitled ‘General rule of interpretation’, has been recognized by the International Court as reflecting customary international law.93 It provides as follows:

  1. 1.  A treaty shall be interpreted in good faith in accordance with the ordinary meaning to be given to the terms of the treaty in their context and in the light of its object and purpose.

  2. (p. 381) 2.  The context for the purpose of the interpretation of a treaty shall comprise, in addition to the text, including its preamble and annexes:

    1. (a)  any agreement relating to the treaty which was made between all the parties in connection with the conclusion of the treaty;

    2. (b)  any instrument which was made by one or more parties in connection with the conclusion of the treaty and accepted by the other parties as an instrument related to the treaty.

  3. 3.  There shall be taken into account, together with the context:

    1. (a)  any subsequent agreement between the parties regarding the interpretation of the treaty or the application of its provisions;

    2. (b)  any subsequent practice in the application of the treaty which establishes the agreement of the parties regarding its interpretation;

    3. (c)  any relevant rules of international law applicable in the relations between the parties.

  4. 4.  A special meaning shall be given to a term if it is established that the parties so intended.

In its Commentary the ILC emphasized that applying this ‘general rule’ would be a single combined operation: hence the use of the singular. The various elements present in any given case would interact.

The first principle stated in VCLT Article 31 is that ‘a treaty shall be interpreted in good faith in accordance with the ordinary meaning to be given to the terms of the treaty’. In Polish Postal Service in Danzig the Permanent Court observed that the postal service which Poland was entitled to establish in Danzig by treaty was not confined to working inside the postal building: ‘postal service’ must be interpreted ‘in its ordinary sense so as to include the normal functions of a postal service’.94 Since then the principle of ordinary meaning has become well established as a fundamental guide to interpreting treaties.

A corollary of the principle of ordinary meaning is the principle of integration: the meaning must emerge in the context of the treaty as a whole (including the text, its preamble and annexes, and any agreement or instrument related to the treaty and drawn up in connection with its conclusion)95 and in the light of its object and purpose.96 Another corollary is the principle of contemporaneity: the language of (p. 382) the treaty must be interpreted in the light of the rules of general international law in force at the time of its conclusion,97 and also in the light of the contemporaneous meaning of terms.98 The doctrine of ordinary meaning involves only a presumption: a meaning other than the ordinary meaning may be established, but the proponent of the special meaning has a burden of proof.99 In complex cases the tribunal will be prepared to make a careful inquiry into the precise object and purpose of a treaty.100

Article 31(3) lists further factors to be taken into account along with the context (as defined in Article 31(2)). The parties may make an agreement regarding the interpretation of the treaty, or the application of its provisions. Such agreements can take various forms; they need not be formal amendments to the treaty.101

Reference may be made to ‘subsequent practice in the application of the treaty which clearly establishes the understanding of all the parties regarding its interpretation’.102 Subsequent practice by individual parties also has some probative value. In a series of important advisory opinions the Court has made considerable use of the subsequent practice of organizations in deciding controversial issues of interpretation.103 Two points arise. The first is that members who were outvoted in the organs concerned may not be bound by the practice. Secondly, the practice of political organs involves elements of discretion and opportunism: what is significant is the reasoning behind the practice which can indicate its legal relevance, if any.104

The rule contained in Article 31(3)(c), requiring interpreters to take into account ‘any relevant rules of international law applicable in the relations between the parties’, places treaties within the wider context of general international law.105 In Oil Platforms the Court described the application of relevant rules of international law as an ‘integral part of the task of interpretation’,106 although the majority judgment has been criticized for the manner in which it then applied substantive customary and Charter (p. 383) rules on the use of force to interpret a treaty provision about freedom of commerce.107 Article 31(3)(c) has been central to the debate around the so-called ‘fragmentation’ of international law,108 forming the basis for arguments promoting systemic integration between different, more or less specialized areas of the law.109 In a world of multiplying institutions with overlapping jurisdiction and choices to make between various sources of applicable law, it is seen as increasingly important to maintain coherence between what may seem self-contained subsystems of law.110 Treaties cannot be interpreted in isolation of the wider context, but at the same time, tribunals should be cautious about using Article 31(3)(c) as a guise for incorporating extraneous rules in a manner that oversteps the boundaries of the judicial function.111

(iv)  Supplementary means of interpretation: VCLT Article 32

The VCLT cautiously qualifies the textual approach by permitting recourse to further means of interpretation in certain circumstances. VCLT Article 32 provides:

Recourse may be had to supplementary means of interpretation, including the preparatory work of the treaty and the circumstances of its conclusion, in order to confirm the meaning resulting from the application of Article 31, or to determine the meaning when the interpretation according to Article 31:

  1. (a)  leaves the meaning ambiguous or obscure; or

  2. (b)  leads to a result which is manifestly absurd or unreasonable.112

In general the Court has refused to resort to preparatory work if the text is sufficiently clear in itself.113 But on a number of occasions the Court has used preparatory work to confirm a conclusion reached by other means.114 Preparatory work is an aid to be employed with care, since its use may detract from the textual approach: moreover, particularly in the case of multilateral agreements, the records of conference (p. 384) proceedings, treaty drafts, etc may be confused or inconclusive.115 The ILC has taken the view that states acceding to a treaty and not taking part in its draft ing cannot claim for themselves the inadmissibility of the preparatory work, which could have been examined before accession.116

Resorting to consideration of the preparatory work in cases referred to in Article 32(b) is not the same as the teleological approach. The textual approach in practice often leaves the decision-maker with a choice of possible meanings, and in exercising that choice it is impossible to keep considerations of policy out of account. Many issues of interpretation are by no means narrow technical inquiries.

At the Vienna Conference the US proposed an amendment to combine Articles 31 and 32, thus giving more scope to preparatory work and the circumstances in which the treaty was concluded. This proposal received little support. In its Commentary the ILC pointed out that the two articles should operate in conjunction, and would not have the effect of drawing a rigid line between ‘supplementary’ and other means of interpretation. At the same time the distinction itself was justified since the elements of interpretation in the first article all relate to the agreement between the parties ‘at the time when or after it received authentic expression in the text’. Preparatory work did not have the same authentic character ‘however valuable it may sometimes be in throwing light on the expression of agreement in the text’.117

(D)  Obligations and Rights for Third States118

The maxim pacta tertiis nec nocent nec prosunt expresses the fundamental principle that a treaty applies only between the parties to it. The VCLT refers to this as the ‘general rule’; it is a corollary of the principle of consent and of the sovereignty and independence of states. Article 34 provides that ‘a treaty does not create either obligations or rights for a third State without its consent’. This falls slightly short of expressing the customary rule, however: besides not creating obligations or rights, treaties cannot infringe the rights of third states without their consent.119 This argument has been central to US objections to the possibility of its nationals becoming subject to the jurisdiction of the International Criminal Court without its consent, through the operation of (p. 385) Article 12(2)(a) of the Rome Statute,120 although the equation of nationals (not being state officials) with the state makes this argument problematic.

The existence and extent of exceptions to the general rule have been controversial. The ILC did not accept the view that treaties creating ‘objective regimes’ (e.g. the demilitarization of a territory by treaty or a legal regime for a major waterway) had a specific place in the law of treaties.121 VCLT Article 35 provides that ‘an obligation arises for a third State from a provision of a treaty if the parties to the treaty intend the provision to be the means of establishing the obligation and the third State expressly accepts that obligation in writing’.

However, two apparent exceptions to the principle exist. First, a rule in a treaty may become binding on non-parties if it becomes a part of international custom.122 Secondly, a treaty may provide for lawful sanctions for violations of the law which are to be imposed on an aggressor state.123 The VCLT contains a reservation in regard to any obligation in relation to a treaty which arises for an aggressor state ‘in consequence of measures taken in conformity with the Charter of the United Nations with reference to the aggression’ (Article 75).

Article 2(6) of the Charter provides that:

The Organization shall ensure that states which are not Members of the United Nations act in accordance with these Principles so far as may be necessary for the maintenance of international peace and security.

Kelsen held the view that the provision created duties, and liabilities to sanctions under the enforcement provisions of the Charter, for non-members.124 Assuming that this was the intention of the draftsmen, the provision could only be reconciled with general principles by reference to the status of the principles in Article 2 as general or customary international law. By now the question is largely academic, given that virtually all states are members of the UN and the Charter is binding on them directly as parties.

More controversial is the conferral of rights on third parties, the stipulation pour autrui. Not infrequently treaties make provisions in favour of specified third states or for other states generally, for example the treaties concerning certain of the major international waterways, including, on one view, the Panama Canal.125 The problem has been to discover when, if at all, the right conferred becomes perfect and enforceable by the third state: is the third state required to give express or implicit assent to the (p. 386) creation of the right before it will benefit, or is it unconditional? Views were divided, but the ILC took the view that the two opposing views did not differ substantially in their practical effects. VCLT Article 36 creates a presumption as to the assent of the third state.

The third state may, of course, disclaim any already inhering right expressly or tacitly through failure to exercise the right. The right of a third state may not be revoked or modified by the parties if it is established that it was intended that this could only occur with the consent of the third state: Article 37(2).

5.  Amendment and Modification of Treaties126

The amendment of treaties depends on the consent of the parties, and the issue is primarily political. However, the lawyer may be concerned with procedures for amendment, as a facet of the large problem of peaceful change in international relations. Many treaties, including the Charter (Articles 108 and 109), provide a procedure for amendment. International organizations have amendment procedures which in some cases show considerable sophistication. In the League Covenant (Article 19) and, less explicitly, in the Charter (Article 14), provision for peaceful change was made as part of a scheme to avoid threats to the peace.

Apart from amendment, a treaty may undergo ‘modification’ when some of the parties conclude an inter se agreement altering the application of the treaty between themselves alone: VCLT Article 41 restricts this capacity in certain cases.

Modification may also result from the conclusion of a subsequent treaty or even the emergence of a new peremptory norm of general international law. The ILC’s Final Draft provided that ‘a treaty may be modified by subsequent practice in the application of the treaty establishing the agreement of the parties to modify its provisions’.127 This was rejected at the Vienna Conference on the ground that such a rule would create instability.128 This result is unsatisfactory. First, Article 39 provides that a treaty may be amended by agreement without requiring any formality for the expression of agreement. Secondly, a consistent practice may provide cogent evidence of common consent to a change. Thirdly, modification of this type occurs in practice. The process of interpretation through subsequent practice is legally distinct from modification, although the distinction is often rather fine.

(p. 387) 6.  Invalidity, Termination, and Suspension of Treaties129

VCLT Part V governs invalidity, termination, and suspension of the operation of treaties. It sets out an exhaustive list of grounds (see Article 42(2)). However, the grounds for termination and the requirements of essential validity do not exhaust the matters relevant to justification for non-performance of obligations. That issue can arise irrespective of validity or termination of the source of obligation, the treaty. The topic of justification belongs to the law of state responsibility,130 expressly reserved by VCLT Article 73.

(A)  Invalidity131

Generally speaking, the validity and continuance in force of a treaty and of consent to be bound is presumed (Article 42), but various matters may give rise to issues of invalidity. Invalidity may be relative (where a treaty is voidable if a party establishes certain grounds) or absolute (where the treaty is void per se). Issues of invalidity tend to arise rarely in practice.

(i)  Violations of Internal Law132

The extent to which constitutional limitations on the treaty-making power can be invoked on the international plane is a matter of controversy. Historically, three main views have received support. According to the first, constitutional limitations determine validity on the international plane.133 Criticism of this view emphasizes the insecurity in treaty-making it would entail. The second view varies from the first in that only ‘notorious’ constitutional limitations are effective on the international plane. The third view is that a state is bound irrespective of internal limitations by consent given by an agent properly authorized according to international law. Some advocates of this view qualify the rule in cases where the other state is aware of the failure to comply (p. 388) with internal law or where the irregularity is manifest. This position, which involves a presumption of competence and excepts manifest irregularity, was approved by the ILC in 1966.134 At the Vienna Conference the draft provision was strengthened, and the result appears in VCLT Article 46.135

(ii)  Defects of authority136

The VCLT provides that if the authority of a representative to express the consent of his state to be bound by a particular treaty has been made subject to a specific restriction, omission to observe the restriction may not be invoked as a ground of invalidity unless the restriction was previously notified to the other negotiating states.

(iii)  Error137

Under VCLT Article 48,138 a state may invoke an error as invalidating its consent to a treaty if the error relates to ‘a fact or situation which was assumed by that State to exist at the time when the treaty was concluded and formed an essential basis of its consent to be bound by the treaty’. However, consistent with the previous law, Article 48(2) provides that this does not apply ‘if the State in question contributed by its own conduct to the error or if the circumstances were such as to put that State on notice of a possible error’.139

(iv)  Fraud140

There are few helpful precedents. The VCLT provides141 that a state which has been induced to enter into a treaty by the fraud of another negotiating state may invoke the fraud as invalidating its consent to be bound by the treaty. Fraudulent misrepresentation of a material fact inducing an essential error is dealt with by the provision relating to error.

The ILC decided that corruption of representatives was not adequately dealt with as a case of fraud142 and an appropriate provision appears as VCLT Article 50.143

(p. 389) (v)  Coercion

Coercion includes coercion of state representatives144 and of states themselves.145 VCLT Article 51 provides that ‘the expression of a State’s consent to be bound by a treaty which has been procured by the coercion of its representative through acts or threats directed against him shall be without legal effect’. The concept of coercion extends to blackmailing threats and threats against the representative’s family.

As for coercion of a state, the ILC considered that Article 2(4) of the UN Charter, together with other developments, justified the conclusion that a treaty procured by the threat or use of force in violation of the Charter shall be void. VCLT Article 52 so provides.146 An amendment with the object of defining force to include any ‘economic or political pressure’ was withdrawn: instead a declaration condemning such pressure appears in the Final Act of the Conference.147

(vi)  Conflict with a peremptory norm148

VCLT Article 53 provides that a treaty is void if at the time of its conclusion it conflicts with a peremptory norm of general international law (ius cogens).149 Further, a treaty becomes void if it conflicts with a peremptory norm of general international law established after the treaty comes into force.150 This does not have retroactive effects on the validity of a treaty. The discussion on the issue of ius cogens proved to be one of the ‘longest, most heated and disorganized debates’ at the Vienna Conference.151 Views differ on whether the VCLT provisions correspond to the existing law on the relationship between treaties and peremptory norms;152 but the answer seems clear enough. A peremptory norm is one from which no derogation is permitted on the part of one or (p. 390) a few states: the form the attempted derogation takes must be irrelevant. Issues raised by peremptory norms are dealt with in more detail in chapter 27.

(B)  Termination and Suspension153

VCLT Part V Section 3 deals with termination and suspension of the operation of treaties. A treaty may of course specify the conditions of its termination, and may provide for denunciation by the parties.154 Where a treaty contains no provisions regarding its termination, the existence of a right of denunciation depends on the intention of the parties, which can be inferred from the terms of the treaty and its subject-matter, but, according to the VCLT, the presumption is that the treaty is not subject to denunciation or withdrawal.155 At least in certain circumstances denunciation is conditional upon a reasonable period of notice. Some important law-making treaties contain no denunciation clause. Treaties of peace are not open to unilateral denunciation.

(i)  War and armed conflict156

Hostile relations do not automatically terminate treaties between the parties to a con-flict.157 Many treaties, including the UN Charter, are intended to be no less binding in case of war, and multipartite law-making agreements such as the Geneva Conventions of 1949 survive war or armed conflict.158 However, in state practice many types of treaty are regarded as at least suspended in time of war, and war conditions may lead to termination of treaties on grounds of impossibility or fundamental change of circumstances. In many respects the law on the subject is uncertain. Thus it is not clear to what extent the illegality of the use or threat of force has had effects on the right (where it may be said to exist) to regard a treaty as suspended or terminated.159

(p. 391) The ILC decided to include the topic ‘effects of armed conflicts on treaties’ in its long-term programme of work in 2000.160 A set of draft articles with commentaries was adopted at second reading in 2011.161

(ii)  Denunciation and termination by agreement

Termination or withdrawal may take place by consent of all the parties.162 Such consent may be implied. In particular, a treaty may be considered as terminated if all the parties conclude a later treaty which is intended to supplant the earlier treaty or if the later treaty is incompatible with its provisions.163 The topic of ‘desuetude’, which is probably not a term of art, is essentially concerned with discontinuance of use of a treaty and its implied termination by consent.164 However, it could extend to the distinct situation of a unilateral renunciation of rights under a treaty. Moreover, irrespective of the agreement of the parties, an ancient treaty may become meaningless and incapable of practical application.

(iii)  Material breach165

It is widely recognized that material breach by one party entitles the other party or parties to a treaty to invoke the breach as the ground of termination or suspension. This option by the wronged party is accepted as a sanction for securing the observance of treaties. However, considerable uncertainty has surrounded the precise circumstances in which such right of unilateral abrogation may be exercised, particularly in respect of multilateral treaties. In practice material breach has rarely been invoked, an exception being Gabčíkovo-Nagymaros Project (Hungary/Slovakia).166

(p. 392) VCLT Article 60167 deals with the matter with as much precision as can be reasonably expected, although its formulation has attracted some criticism.168 Paragraphs 1 and 2 set out what parties to bilateral and multilateral treaties are entitled to do in response to a material breach by another party. Paragraph 3 defines a material breach as a repudiation of the treaty not sanctioned by the VCLT, or the violation of a provision essential to the accomplishment of the object or purpose of the treaty.169 It should be observed that the focus here is on the importance of the provision violated, not the magnitude of the breach.170 Paragraph 4 stipulates that the first three paragraphs are without prejudice to any provision in the treaty applicable in the event of a breach, and paragraph 5 excludes the application of the first three paragraphs to ‘provisions relating to the protection of the human person contained in treaties of a humanitarian character’.

A state may by its own conduct prejudice its right to terminate a treaty on the ground of material breach.171

(iv)  Supervening impossibility of performance172

The VCLT provides that a party ‘may invoke the impossibility of performing a treaty as a ground for terminating it if the impossibility results from the permanent disappearance or destruction of an object indispensable for the execution of the treaty’.173 Situations envisaged include the submergence of an island, the drying up of a river, or destruction of a railway, by an earthquake, or other disaster. The effect of impossibility is not automatic, and a party must invoke the ground for termination. Impossibility of performance may not be invoked by a party to the relevant treaty when it results from that party’s own breach of an obligation flowing from the treaty.174

(v)  Fundamental change of circumstances175

The principles by which fundamental change of circumstances may be invoked as a ground for terminating or withdrawing from a treaty are expressed in VCLT Article 62. (p. 393) An example of a fundamental change would be the case where a party to a military and political alliance, involving exchange of military intelligence and information, has a change of government incompatible with the basis of alliance. The provision reflects the doctrine of rebus sic stantibus, which involves the implication of a term that the obligations of an agreement would end if there had been a change of circumstances. As in municipal systems, so in international law it is recognized that changes frustrating the object of an agreement, even if not amounting to actual impossibility, may justify its termination. Some jurists dislike the doctrine, regarding it as a source of insecurity of obligations, more especially in the absence of a system of compulsory jurisdiction. But it has generally been applied very conservatively, as it was in Free Zones.176 Further the VCLT excludes boundary treaties from the operation of the principle in order to avoid an obvious source of threats to the peace.

In Fisheries Jurisdiction (UK v Iceland) the International Court accepted VCLT Article 62 as a statement of customary law but decided that the dangers to Icelandic interests resulting from new fishing techniques ‘cannot constitute a fundamental change with respect to the lapse or subsistence’ of the jurisdictional clause in a bilateral agreement.177 In Gabčíkovo-Nagymaros, Hungary specified profound changes of a political character, the Project’s diminishing economic viability, the progress of environmental knowledge, and the development of new norms and prescriptions of international environmental law, as grounds entitling it to invoke the fundamental change of circumstances principle. The Court recalled its findings in Fisheries Jurisdiction and rejected the Hungarian argument, holding that:

The changed circumstances advanced by Hungary are, in the Court’s view, not of such a nature, either individually or collectively, that their effect would radically transform the extent of the obligations still to be performed in order to accomplish the Project. A fundamental change of circumstances must have been unforeseen; the existence of the circumstances at the time of the Treaty’s conclusion must have constituted an essential basis of the consent of the parties to be bound by the Treaty.178

Referring to the language of VCLT Article 62, the Court concluded that ‘the stability of treaty relations requires that the plea of fundamental change of circumstances be applied only in exceptional cases’.179 In contrast to this generally accepted position, the Court of Justice of the European Communities applied a relaxed interpretation of the rebus doctrine to uphold the suspension of the EC–Yugoslavia Cooperation Agreement in the case of Racke v Hauptzollamt Mainz.180 It conceded that the (p. 394) Commission could have continued to grant tariff concessions after the outbreak of hostilities, but noted that impossibility of performance was not required and that there was ‘no point’ in continuing to grant preferences in circumstances where Yugoslavia was breaking up.181

Treaties may also be affected when one state succeeds wholly or in part to the legal personality and territory of another. The conditions under which the treaties of the latter survive depend on many factors, including the precise form and origin of the ‘succession’ and the type of treaty concerned.182

(C)  Procedure and Consequences183

The consequences of invalidity, termination, and suspension will depend on the grounds relied upon. Certain grounds of invalidity must be invoked by a party184 and so the treaties concerned are not void but voidable. These grounds are: incompetence under internal law, restrictions on authority of representative, error, fraud, and corruption of a representative. The same is true of certain grounds of termination—material breach, impossibility, and fundamental change of circumstances. On the other hand a treaty is void in case of coercion of a state (invalidity), and conflict with an existing or emergent peremptory norm (invalidity or termination). Consent to be bound by a treaty procured by coercion of the representative of a state ‘shall be without any legal effect’ (Article 51, invalidity). The rules governing separability of treaty provisions (Article 44), that is, the severance of particular clauses affected by grounds for invalidating or terminating a treaty, do not apply to the cases of coercion of a representative, coercion of a state, or conflict with an existing peremptory norm.185 Articles 69 to 72 deal with the consequences of invalidity, termination, or suspension.


1  Harvard Research (1935) 29 AJIL Supp; McNair, The Law of Treaties (1961); Jennings (1967) 121 Hague Recueil 527; Elias, The Modern Law of Treaties (1974); Sinclair, The Vienna Convention on the Law of Treaties (2nd edn, 1984); Rosenne, Developments in the Law of Treaties, 1945–1986 (1989); Thirlway (1991) 62 BY 2; Thirlway (1992) 63 BY 1; Reuter, Introduction to the Law of Treaties (2nd edn, 1995); Aust, Modern Treaty Law and Practice (2nd edn, 2007); Villiger, Commentary on the 1969 Vienna Convention on the Law of Treaties (2009); Villiger (2009) 344 Hague Recueil 9; Corten & Klein (eds), The Vienna Conventions on the Law of Treaties (2011).

2  In addition to its work on interstate treaties, the ILC produced draft articles on treaties of international organizations, which became VCLT II, 21 March 1986, 25 ILM 543 (not yet in force). In 2011 it completed an enormous Guide to Practice on Reservations to Treaties: A/CN.4/L.779, 19 May 2011. It is working on temporal aspects of treaties: www.untreaty.un.org/ilc/summaries/1_11.htm.

3  The principal items are: Reports by Brierly, ILC Ybk 1950/II, 222; ILC Ybk 1951/II, 1; ILC Ybk 1952/ II, 50; Lauterpacht, ILC Ybk 1953/II, 90; ILC Ybk 1954/II, 123; Fitzmaurice, ILC Ybk 1956/II, 104; ILC Ybk 1957/II, 16; ILC Ybk 1958/II, 20; ILC Ybk 1960/II, 69; Waldock, ILC Ybk 1962/II, 27; ILC Ybk 1963/II, 36; ILC Ybk 1964/II, 4; ILC Ybk 1965/II, 3; ILC Ybk 1966/II, 1; ILC Final Report and Draft Articles, ILC Ybk 1966/II, 172.

4  22 May 1969, 1155 UNTS 331. See Kearney & Dalton (1970) 64 AJIL 495.

5  Villiger (2009) 24–7.

6  Under Art 4, VCLT only applies to treaties concluded between states all of which at that time were already parties to VCLT. Since only 111 states are parties, this means in effect that VCLT does not apply to major multilateral treaties. In practice it is applied as customary international law in any event.

7  Legal Consequences for States of the Continued Presence of South Africa in Namibia (South West Africa) notwithstanding Security Council Resolution 276 (1970), ICJ Reports 1971 p 16, 47. Also: Appeal relating to the Jurisdiction of the ICAO Council (India v Pakistan), ICJ Reports 1972 p 46, 67; Fisheries Jurisdiction (UK v Iceland), ICJ Reports 1973 p 3, 18; Sovereignty over Pulau Ligitan and Pulau Sipidan (Indonesia/ Malaysia), ICJ Reports 2002 p 625, 645–6; IranUS, Case No A/18 (1984) 75 ILR 175, 187–8; Lithgow and Others (Shipbuilding Nationalization) (1986) 75 ILR 438, 483–4; Restrictions to the Death Penalty (1983) 70 ILR 449, 465–71; Asian Agricultural Products Ltd v Republic of Sri Lanka (1990) 106 ILR 416, 437–46; Ethyl Corporation v Government of Canada (1998) 122 ILR 250, 278–80; Pope and Talbot v Canada (2001) 122 ILR 293, 328.

8  E.g. R v Minister of Agriculture, ex parte SP Anastasiou (Pissouri) Ltd (1994) 100 ILR 257, 298–9; Opel Austria v Council of the EU (1997) 113 ILR 295, 323–4; Racke v Hauptzollamt Mainz (1998) 117 ILR 399, 437–43; Case C-268/99 Jany v Staatssecretaris van Justitie [2001] ECR I-8615, para 35; Joined Cases C-402/05 P and C-415/05 P Kadi & Al Barakaat International Foundation v Council & Commission [2008] ECR I-06351, §291. Further: Kuijper (1998) 25 Legal Issues of Economic Integration 1; Klabbers (1999) 30 NYIL 45; Verwey, The European Community and the European Union and the International Law of Treaties (2004).

9  E.g. US—Gasoline, WTO Doc WT/DS2/AB/R, 29 April 1996, 16–17; US—Gambling, WTO Doc WT/ DS285/AB/R, 7 April 2005, 51. Further: van Damme, Treaty Interpretation by the WTO Appellate Body (2009).

10  79–1 (France): 19.

11  VCLT II; Gaja (1987) 58 BY 253; Zemanek, in Hafner et al (eds), Liber Amicorum Ignaz Seidl-Hohenveldern (1998) 843; Menon, Law of Treaties between States and International Organizations (1992); Brölmann, in Klabbers & Lefeber (eds), Essays on the Law of Treaties (1998) 121; Footer, in Orakhelashvili & Williams (eds), 40 Years of the Vienna Convention on the Law of Treaties (2010) 183; Tomuschat, in Cannizzaro (ed), The Law of Treaties Beyond the Vienna Convention (2011) 206.

12  Vienna Convention on Succession of States in Respect of Treaties, 22 August 1978, 1946 UNTS 3; also chapter 19.

14  ILC Ybk 1962/II, 161.

15  On the concept of a treaty: Widdows (1979) 50 BY 117; Virally, in Diez et al (eds), Festschrift für Rudolf Bindschedler (1980) 159; Thirlway (1991) 62 BY 1, 4–15; Klabbers, The Concept of Treaty in International Law (1996); Fitzmaurice (2002) 73 BY 141.

16  The conclusion of treaties in simplified form is increasingly common. Many treaties are made by an exchange of notes, the adoption of agreed minutes, etc. See ILC Ybk 1966/II, 188; Aust (2nd edn, 2007) 102; Corten & Klein, Les Conventions de Vienne Sur le Droit des Traités (2006) 343; Villiger, Commentary (2009) 181. Also: Aegean Sea Continental Shelf (Greece v Turkey), ICJ Reports 1978 p 3, 38–44; Military and Paramilitary Activities in and against Nicaragua (Nicaragua v US), ICJ Reports 1986 p 14, 130–2; Maritime Delimitation and Territorial Questions between Qatar and Bahrain (Qatar v Bahrain), Jurisdiction and Admissibility, ICJ Reports 1994 p 112, 120–2.

17  See Mann (1957) 33 BY 20; Mann (1959) 35 BY 34; Fitzmaurice (2002) 73 BY 141, 168; cf Diverted Cargoes (1955) 12 RIAA 53, 70.

18  McNair (1961) 739–54. On the special role of multilateral treaties: Lachs (1957) 92 Hague Recueil 229, 233–41; Crawford (2006) 319 Hague Recueil 325, 349–420.

19  McNair (1961) 743–9.

20  VCLT, Art 62(2) (fundamental change of circumstances rule inapplicable to boundary treaties).

21  ILC Ybk 1966/II, 219.

22  Dehaussy, in Recueil d’études en hommage à Guggenheim (1968) 305; Gardiner, Treaty Interpretation (2008) 142.

23  For the history: Lauterpacht, Private Law Sources and Analogies of International Law (1927) 156–9, §70.

24  ILC Ybk 1962/II, 161.

25  Draft Articles, I, ILC Ybk 1962/II, 167–9 (Art 8); Waldock (1962) 106 Hague Recueil 1, 53–8.

26  ILC Ybk 1966/II, 200; UN Secretariat Working Paper, A/CN.4/245, 23 April 1971, 131–4. Also: Lukashuk (1972) 135 Hague Recueil 231.

27  Generally: Aust (1986) 35 ICLQ 787.

28  Temple of Preah Vihear (Cambodia v Thailand), Preliminary Objections, ICJ Reports 1961 p 17, 31–2.

29  Qatar v Bahrain, Jurisdiction and Admissibility, ICJ Reports 1994 p 112, 120–2; Aust (2nd edn, 2007) 16–31.

30  ILC Ybk 1966/II, 190–1 (Art 3).

31  Aust (2nd edn, 2007) 32–57; E Lauterpacht, in Flume (ed), Festschrift für FA Mann (1977) 381; Thirlway (1991) 63 BY 1, 18–19.

32  Aust (2nd edn, 2007) 16–31, esp 23–7.

33  VCLT, Arts 7–11; Waldock, ILC Ybk 1962/II, 38ff; ILC Ybk 1966/II, 189, 193–7; Watts (1994) 247 Hague Recueil 10, 19; Sabel, Procedure at International Conferences(2nd edn, 2006) 58–67. Further: Armed Activities on the Territory of the Congo (New Application: 2002) (DRC v Rwanda), Jurisdiction and Admissibility, ICJ Reports 2006 p 6, 27–9.

34  Heads of state, heads of government, and foreign ministers are also not required to furnish evidence of their authority: VCLT, Art 7(2). Further: Aust (2nd edn, 2007) 75–83.

35  ICJ Reports 2002 p 303, 430.

36  Application of the Convention on the Prevention and Punishment of the Crime of Genocide (Bosnia and Herzegovina v Yugoslavia), Preliminary Objections, ICJ Reports 1996 p 595, 661–2.

37  VCLT, Art 10.

38  ILC Ybk 1962/II, 171. But cf Lauterpacht, ILC Ybk 1953/II, 108–12; Fitzmaurice, ILC Ybk 1956/II, 112–13, 121–2. Also: Rosenne (2000) 4 EPIL 932; Kolb (2004) 51 NILR 185; Corten & Klein (2006) 343–538; Aust (2nd edn, 2007) 94–102; Villiger, Commentary (2009) 181–228.

39  VCLT, Art 18; Certain German Interests in Polish Upper Silesia (1926) PCIJ Ser A No 7, 30; Aust (2nd edn, 2007) 116–21; Palchetti, in Cannizzaro (2011) 25. Note Art 18(a): if a state that has signed a treaty makes it clear that it does not intend to ratify it, it is released from any obligations under Art 18 and its signature has no legal effect. The US relied on this to ‘unsign’ the ICC Statute (17 July 1998, 2187 UNTS 3) in May 2002, by lodging a note with the UN to the effect that it did not intend to become a party: Swaine (2003) 55 Stanford LR 2061.

40  VCLT, Art 14; for other means of expressing consent to be bound: VCLT, Arts 11–17.

41  Cameroon v Nigeria, ICJ Reports 2002 p 303, 429–30.

42  Draft Articles, I, ILC Ybk 1962/II, 161, 171–3 (Arts 1(1)(d), 12); Waldock, ILC Ybk 1962/II, 48–53. Also: ILC Final Report and Draft Articles, ILC Ybk 1966/II, 187–9, 195–9, 201 (Arts 2(1)(b), 10–11, 13).

43  McNair (1961) 153–5.

44  VCLT, Arts 11, 13; Fitzmaurice, in Klabbers & Lefeber (1998) 59; Fitzmaurice & Hollis (2005) 23 Berkeley JIL 137.

45  VCLT, Art 24(2). The International Court has described Art 24 as declaratory of the general rule: Cameroon v Nigeria, Preliminary Objections, ICJ Reports 1998 p 275, 293–4; Right of Passage over Indian Territory (Portugal v India), Preliminary Objections, ICJ Reports 1957 p 125, 145–7.

46  VCLT, Arts 76–7; Rosenne (1967) 61 AJIL 923; Rosenne (1970) 64 AJIL 838.

47  The first of Wilson’s Fourteen Points Address, delivered at a joint session of Congress on 8 January 1918, called for ‘open covenants of peace, openly arrived at’: US Department of State, Papers Relating to the Foreign Relations of the United States 1918—Supplement 1, The World War (1933) 12, 15; Schwietzke, ‘Fourteen Points of Wilson (1918)’ (2007) MPEPIL.

48  If an agreement is between international legal persons it is registrable even if governed by a particular municipal law; cf Higgins (1963) 329.

49  South West Africa (Ethiopia v South Africa; Liberia v South Africa), Preliminary Objections, ICJ Reports 1962 p 319, 359–60 (Judge Bustamante), 420–2 (Judge Jessup); cf 503 (Judges Spender & Fitzmaurice, joint diss).

50  VCLT, Arts 19–23; further: Lauterpacht, ILC Ybk 1953/II, 123–36; Fitzmaurice (1953) 2 ICLQ 1; McNair (1961) ch 4; Bishop (1961) 103 Hague Recueil 249; Draft Articles, I, ILC Ybk 1962/II, 161, 163, 175–82 (Arts 1(1)(f), 18–22); Anderson (1964) 13 ICLQ450; Waldock, ILC Ybk 1966/II, 27, 60–8; ILC Final Report and Draft Articles, ILC Ybk 1966/II, 189–90, 202–9 (Arts 2(1)(d), 16–20); Jennings (1967) 121 Hague Recueil 534; Bowett (1976–77) 48 BY 67; Sinclair (2nd edn, 1984) 51–82; Greig (1995) 16 AYIL 21; Villiger (2009) 344 Hague Recueil 9, 77–112; Pellet & Müller, in Cannizzaro (2011) 37; Corten & Klein (2011) 405–627. Further: reports of the Special Rapporteur on Reservations to Treaties (Pellet), available at www.untreaty.un.org/ilc/summaries/1_8.htm and ILC Report 2011, GAOR, 66th Session, Supp No 10, A/66/10, 12–49.

51  E.g. the Swiss declaration regarding ECHR, 4 November 1950, ETS 5, Art 6(1): Belilos v Switzerland (1988) 88 ILR 635, 636. On the difficulty in some cases of distinguishing interpretative declarations from reservations: ibid, 663–6.

52  On this contractual conception of treaties, a reservation would constitute a counter-offer requiring a new acceptance, failing which the state making the counter-offer would not become a party to the treaty. See Reservations to the Convention on the Prevention and Punishment of the Crime of Genocide, ICJ Reports 1951 p 15, 21, 24.

53  Ibid, 29.

54  ILC Ybk 1951/II, 128–31.

55  GA Res 598(VI), 12 January 1952.

56  GA Res 1452A(XIV), 7 December 1959.

57  Draft Articles, I, ILC Ybk 1962/II, 175–81 (Arts 18(1)(d) and 20(2)). The Commission rejected a ‘collegiate’ system which would require acceptance of the reservation by a given proportion of the other parties: cf Anderson (1964) 13 ICLQ 450.

58  Special provisions concerning the making of reservations may present difficult problems of interpretation. See UK-French Continental Shelf (1977) 54 ILR 6, 41–57; Bowett (1976–77) 48 BY 67.

59  Waldock, ILC Ybk 1962/II, 65–6; ILC Ybk 1966/II, 205; Sinclair (1970) 19 ICLQ 53.

60  E.g. Bowett (1976–77) 48 BY 67, 70–5; Redgwell (1993) 64 BY 245.

61  See Chinkin et al (Gardner ed), Human Rights as General Norms and a State’s Right to Opt Out (1997).

62  Belilos v Switzerland (1988) 88 ILR 635. Further: Cameron & Horn (1990) 33 GYIL 69; Marks (1990) 39 ICLQ 300.

63  Loizidou v Turkey, Preliminary Objections (1995) 103 ILR 622. For a similar approach under the Inter-American system: Radilla-Pacheco v Mexico, IACtHR C/209, 23 November 2009, §§299–312.

64  CCPR, General Comment 24 (1994) CCPR/C/21/Rev.1/Add.6. The UK government was critical: (1995) 66 BY 655. Also: Hampson, E/CN.4/Sub.2/1999/28, 28 June 1999; Simma, in Hafner et al (1998) 659; Helfer (2002) 102 Col LR 1832. Further: Armed Activities (2002 Application) (DRC v Rwanda), Jurisdiction and Admissibility, ICJ Reports 2006 p 6, 69–70 (Judges Higgins, Kooijmans, El Araby, Owada & Simma).

65  ILC Report 2011, GAOR, 66th Session, Supp No 10, A/66/10, 12–51 and Add.1.

66  A/CN.4/647/Add.1, 6 June 2011, 15–20.

67  A/66/10/Add.1, commentary to Guideline 4.5.2.

68  Ibid, Guideline 4.5.3, §2.

69  Ibid, Guideline 4.5.3, §1.

70  Ibid, commentary to Guideline 4.5.3.

71  VCLT, Art 42. Also: Draft Articles, II, ILC Ybk 1963/II, 189–90 (Art 30); ILC Final Report and Draft Articles, ILC Ybk 1966/II, 236–7 (Art 39).

72  VCLT, Art 26; ILC Final Report and Draft Articles, ILC Ybk 1966/II, 210–11 (Art 23); Villiger, Commentary (2009) 361–8; Corten & Klein (2011) 659–87.

73  And this despite General de Gaulle’s maxim, ‘Treaties are like roses and young girls. They last while they last’: Time, 12 July 1963.

74  VLCT, Art 27; Villiger, Commentary (2009) 369–75; Corten & Klein (2011) 688–717.

75  VCLT, Art 28; Villiger, Commentary (2009) 379–86; Corten & Klein (2011) 718–30.

76  VCLT, Art 29; Villiger, Commentary (2009) 387–94; Corten & Klein (2011) 731–63.

77  Generally: Draft Articles, III, ILC Ybk 1964/II, 185–92 (Art 63); ILC Final Report and Draft Articles, ILC Ybk 1966/II, 214–17 (Art 26); Jenks (1953) 30 BY 401; Sciso (1987) 38 ÖZfÖR 161; Binder, Treaty Conflict and Political Contradiction (1988); Kohen (2000) 106 RGDIP 577; Sadat-Akhavi, Methods of Resolving Conflicts between Treaties (2003); Villiger, Commentary (2009) 395–411; Klabbers, in Cannizzaro (2011) 192.

78  TFEU (2008) OJEU C 115/47.

79  Al Jedda v UK [2011] ECtHR 27021/08, §§105–9.

80  McNair (1961) chs 20–9; Fitzmaurice (1971) 65 AJIL 358; Yasseen (1976) 151 Hague Recueil 1; Thirlway (1991) 62 BY 1, 16–75; Thirlway (2007) 77 BY 1; Torres Bernárdez, in Hafner et al (1998) 721; Berman (2004) 29 Yale JIL 315; Kolb, Interprétation et creation du droit international (2006); French (2006) 55 ICLQ 281; Linderfalk, On the Interpretation of Treaties (2007); Gardiner (2008); Orakhelashvili, The Interpretation of Acts and Rules in Public International Law (2008); Villiger (2009) 344 Hague Recueil 9, 113–34; van Damme (2009); Villiger, in Cannizzaro (2011) 105; Corten & Klein (2011) 804–86.

81  Certain Expenses of the United Nations (Article 17, paragraph 2, of the Charter), ICJ Reports 1962 p 151, 163. Also: Navigational and Related Rights (Costa Rica v Nicaragua), ICJ Reports 2009 p 213, 237.

82  For interpretation in the World Court pre-VCLT: Fitzmaurice (1951) 28 BY 1.

83  On interpretation of treaties authenticated in two or more languages: Art 33; James Buchanan and Co Ltd v Babco(UK) Ltd[1977] AC 141; Young Loan(1980)59 ILR 494; Nicaragua, Jurisdiction and Admissibility, ICJ Reports 1984 p 392, 522–3 (Judge Ago), 537–9 (Judge Jennings), 575–6 (Judge Schwebel, diss); LaGrand (Germany v US), ICJ Reports 2001 p 466, 502.

84  As the International Court put it in 1950, ‘[i]f the relevant words in their natural and ordinary meaning make sense in their context, that is an end of the matter’: Competence of the General Assembly for the Admission of a State to the United Nations, ICJ Reports 1950 p 4, 8. Also: Territorial Dispute (Libya/Chad), ICJ Reports 1994 p 6, 21–2; Qatar v Bahrain, Jurisdiction and Admissibility, ICJ Reports 1995 p 6, 18; Pulau Ligitan/Sipadan, ICJ Reports 2002 p 625, 645; Genocide (Bosnia and Herzegovina v Serbia and Montenegro), ICJ Reports 2007 p 43, 109–10. Further: Fitzmaurice (1951) 28 BY 1, 1–28; Fitzmaurice (1957) 33 BY 203, 203–38; Thirlway (1991) 62 BY 1, 18–37; Gardiner (2008) 13–17.

85  E.g. Territorial Jurisdiction of the International Commission of the River Oder (1929) PCIJ Ser A No 23, 261. On restrictive interpretation generally: Lauterpacht (1949) 26 BY 48; Crook (1989) 83 AJIL 278, 304–7; Orakhelashvili (2003) 14 EJIL 529; Crema (2010) 21 EJIL 681.

86  E.g. Navigational Rights, ICJ Reports 2009 p 213, 237–8.

87  Generally: Waldock, in Mélanges Reuter, 535; Klabbers (2001) 34 Vand JTL 283; Jonas & Saunders (2010) 43 Vand JTL 565, 581.

88  ICJ Reports 2009 p 213, 343.

89  International Status of South West Africa, ICJ Reports 1950 p 128; South West Africa, Preliminary Objections, ICJ Reports 1962 p 319; Namibia, ICJ Reports 1971 p 16, 47–50. Also: Certain Expenses, ICJ Reports 1962 p 151, 198–215 (Judge Fitzmaurice).

90  See Golder v UK (1975) 57 ILR 200, 245–6. Also: Letsas, A Theory of Interpretation of the European Convention on Human Rights (2008); Gros-Espiell, in Nieto Navia, La Corte y el Sistema Interamericanos de Derechos Humanos (1994) 223.

91  ILC Ybk 1966/II, 219.

92  ILC Ybk 1966/II, 218–19.

93  E.g. Arbitral Award of 31July 1989(Guinea-Bissau v Senegal), ICJ Reports 1991 p 53, 70; Pulau Ligitan/Sipadan, ICJ Reports 2002 p 625, 645; Avena and Other Mexican Nationals (Mexico v US), ICJ Reports 2004 p 12, 48; Genocide (Bosnia and Herzegovina v Serbia and Montenegro), ICJ Reports 2007 p 43, 109–10.

94  (1925) PCIJ Ser B No 11, 37.

95  VCLT, Art 31(2); further: Competence of the ILO to Regulate the Conditions of the Labour of Persons Employed in Agriculture (1922) PCIJ Ser B Nos 2 and 3, 23; Free Zones of Upper Savoy and the District of Gex (1932) Ser A/B No 46, 140; South West Africa, Preliminary Objections, ICJ Reports 1962 p 319, 335; Young Loan (1980) 59 ILR 494, 534–40, 556–8; Arbitral Award of 31 July 1989, ICJ Reports 1991 p 53. Also: Bernhardt (1967) 27 ZaöRV 491, 498; Gardiner (2008) 165–6.

96  Rights of Nationals of the United States of America in Morocco (France v US), ICJ Reports 1952 p 176, 183–4, 197–8; Pulau Ligitan/Sipadan, ICJ Reports 2002 p 625, 645–6, 651–3. See also Sur, L’Interpretation en droit international public (1974) 227–31; Reuter, in Dinstein & Tabory (eds), International Law at a Time of Perplexity (1989) 623, 628; Jennings, in Bedjaoui (ed), International Law Achievements and Prospects (1991) 135, 145; Buffard & Zemanek (1998) 3 Austrian RIEL 311, 319; Linderfalk (2007) 205.

97  Grisbadarna (1909) 11 RIAA 159; Namibia, ICJ Reports 1971 p 16, 31.

98  US Nationals in Morocco, ICJ Reports 1952 p 176, 189.

99  For critical comment on the concept of natural or plain meaning: Lauterpacht, Development (1958) 52–60.

100  Gabčíkovo-Nagymaros Project (Hungary/Slovakia), ICJ Reports 1997 p 7, 35–46.

101  Aust (2nd edn, 2007) 238–41.

102  ILC Ybk 1966/II, 221; Air Transport Services Agreement (US v France) (1964) 38 ILR 182, 245–8, 256–8; Young Loan (1980) 59 ILR 494, 541–3; ibid, 573–4 (Robinson, Bathurst & Monguilan, diss). Also: Fitzmaurice (1951) 28 BY 1, 20–1; Fitzmaurice (1957) 33 BY 203, 223–5 (commending subsequent practice for its ‘superior reliability’ as an indication of meaning); Aust (2nd edn, 2007) 241–3; Villiger, Commentary (2009) 431–2.

103  Admissions, ICJ Reports 1950 p 4, 9; Constitution of the Maritime Safety Committee of the Inter-Governmental Maritime Consultative Organization, ICJ Reports 1960 p 150, 167–71; Certain Expenses, ICJ Reports 1962 p 151. Further: Engel (1967) 16 ICLQ 865; Amerasinghe (1994) 65 BY 175.

104  Certain Expenses, ICJ Reports 1962 p 151, 187 (Judge Spender); 201–3 (Judge Fitzmaurice); Namibia, ICJ Reports 1971 p 16, 52–3.

105  Aust (2nd edn, 2007) 243–4.

106  Oil Platforms (Iran v US), ICJ Reports 2003 p 161, 182–3.

107  In her separate opinion Judge Higgins accused the majority of invoking the concept of treaty interpretation to displace the applicable law, with the result that the text of the treaty itself was ignored: ibid, 237–8 (Judge Higgins).

108  On fragmentation: e.g. Simma (2004) 25 Mich JIL 845; Pauwelyn (2004) 25 Mich JIL 903; Fragmentation of International Law: Difficulties Arising From The Diversification and Expansion of International Law, Report of the Study Group of the ILC, 58th Session, A/CN.4/L.682, 13 April 2006; Buffard, in Buffard et al (eds), International Law between Universalism and Fragmentation (2008) 13.

109  McLachlan (2005) 54 ICLQ 279.

110  E.g. Dupuy (2002) 297 Hague Recueil 9; Higgins (2003) 52 ICLQ 1; Pauwelyn, Conflict of Norms in Public International Law (2003); Simma & Pulkoswki (2006) 17 EJIL 483; Higgins (2006) 55 ICLQ 791; Vanneste, General International Law before Human Rights Courts (2010).

111  French (2006) 55 ICLQ 281.

112  ILC Ybk 1966/II, 222–3; Schwebel, in Makarczyk (ed), Theory of International Law at the Threshold of the21stCentury(1996) 541; Gardiner (1997) 46 ICLQ 643; Klabbers (2003) 50 NILR267; Sbolci, in Cannizzaro (2011) 145. See also Genocide (Bosnia and Herzegovina v Serbia), ICJ Reports 2007 p 43, 109–10.

113  Conditions of Admission of a State to Membership in the United Nations (Article 4 of the Charter), ICJ Reports 1948 p 57, 63; (Second) Admissions, ICJ Reports 1950 p 4, 8; Fitzmaurice (1951) 28 BY 1, 10–13; (1957) 33 BY 203, 215–20.

114  See Convention of 1919concerning the Work of Women at Night (1932) PCIJ Ser A/B No 50, 380; Libya/ Chad, ICJ Reports 1994 p 6, 27–8. See also Banković v Belgium (2001) 123 ILR 94, 110–11.

115  For an interpretation that constituted a manifest inconsistency between the text of the treaty and its preparatory work: González(‘Cotton Field’) v Mexico, IACtHR, C/205, 16 November 2009, §73: ‘inasmuch as it relates to a subsidiary method of interpretation, the preparatory works are completely insufficient to provide solid grounds to reject the interpretation made of Article 12 of the Convention of Belém do Pará.’

116  Differing thus from River Oder (1929) PCIJ Ser A No 23. Further: Sinclair (1963) 12 ICLQ 512; Arbitral Commission on Property, etc, in Germany (1966) 29 ILR 442, 460.

117  ILC Ybk 1966/II, 219–20.

118  VCLT, Arts 34–8; Draft Articles, III, ILC Ybk 1964/II, 180–5 (Arts 58–62); ILC Final Report and Draft Articles, ILC Ybk 1966/II, 226–31 (Arts 30–4); Lauterpacht, Development (1958) 306–13; Sinclair (2nd edn, 1984) 98–106; Chinkin, Third Parties in International Law (1993) 25–114; Tomuschat (1993) 241 Hague Recueil 195; Villiger, Commentary (2009) 465–504; Corten & Klein (2011) 887–960.

119  See O’Keefe (2010) Cam RIA 1, 9.

120  ICC Statute, 17 July 1998, 2187 UNTS 3 (currently 119 parties). For analysis of US arguments about the ‘third-party effect’ of the ICC Statute, see O’Keefe (2010) Cam RIA 1.

121  See McNair (1961) 310. Cf Vienna Convention on the Succession of States in Respect of Treaties, Arts 11, 12; Gabčíkovo-Nagymaros, ICJ Reports 1997 p 7, 70–3; Klabbers (1998) 11 LJIL 345, 352–5.

122  VCLT, Art 38; ILC Final Report and Draft Articles, ILC Ybk 1966/II, 230–1 (Art 34).

123  ILC Ybk 1966/II, 227.

124  The Law of the United Nations (1951) 106–10; cf Bindschedler (1963) 108 Hague Recueil 307, 403–7. Also: McNair (1961) 216–18.

125  Ibid, 265–8.

126  VCLT, Arts 39–41; Draft Articles, III, ILC Ybk 1964/II, 193–9 (Arts 65–8); ILC Final Report and Draft Articles, ILC Ybk 1966/II, 231–6 (Arts 35–8); Handbook of Final Clauses, ST/LEG/6, 130–52; Hoyt, The Unanimity Rule in the Revision of Treaties (1959); Zacklin, The Amendment of the Constitutive Instruments of the United Nations and Specialized Agencies (1968, repr 2005); Kontou, The Termination and Revision of Treaties in Light of New Customary International Law (1994); Bowman (1995) 44 ICLQ 540; Frowein, in Hafner et al (1998) 201; Villiger, Commentary (2009) 507–38; Corten & Klein (2011) 961–1011.

127  ILC Ybk 1966/II, 236 (Art 38).

128  GAOR, 1st Session, 207–15. Also: Kearney & Dalton (1970) 64 AJIL 495, 525.

129  McNair (1961) chs 30–5; Elias (1971) 134 Hague Recueil 333; Haraszti, Some Fundamental Problems of the Law of Treaties (1973) 229–425; Rozakis (1974) 16 AdV 150; Jiménez de Aréchaga (1978) 159 Hague Recueil 1, 59–85; Ruda, in Dinstein & Tabory (1989) 61; Conforti & Labella (1990) 44 EJIL 44; Thirlway(1992) 63 BY 63; Corten & Klein (2006) 1593–2587; Villiger, Commentary (2009) 541–798; Corten & Klein (2011) 1015–642.

130  On the relationship between the law of treaties and the law of state responsibility generally: Dupuy (1997) 43 AFDI 7; Lefeber (1998) 11 LJIL 609; Crawford & Olleson (2000) 21 AYIL 55; Simma & Pulkowski (2006) 17 EJIL 483; Verhoeven, in Crawford, Pellet & Olleson (eds), The Law of International Responsibility (2010) 105.

131  McNair (1961) 206–36; Aust (2nd edn, 2007) 312–23; Corten & Klein (2011) 1090–235.

132  See de Visscher, De la Conclusion des traités internationaux (1943) 219–87; Lauterpacht, ILC Ybk 1953/II, 141–6; McNair (1961) ch 3; Waldock, ILC Ybk 1963/II, 41–6; ILC Ybk 1963/II, 190–3; ILC Final Report and Draft Articles, ILC Ybk 1966/II, 240–2; de Visscher (1972) 136 Hague Recueil 1, 94–8; Meron (1978) 49 BY 175; Villiger, Commentary (2009) 583–94.

133  This was the position of the ILC in 1951: ILC Ybk 1951/II, 73.

134  ILC Ybk 1966/II, 240–2.

135  Cameroon v Nigeria, ICJ Reports 2002 p 303, 430.

136  VCLT, Art 47. See Draft Articles, II, ILC Ybk 1963/II, 193; Waldock, ILC Ybk 1963/II, 46–7; ILC Final Report and Draft Articles, ILC Ybk 1966/II, 242–3 (Art 44); Villiger, Commentary (2009) 595–602. Further: Phillips Petroleum Co, Iran v Iran, National Iranian Oil Co (1982) 70 ILR 483, 486; Amoco Iran Oil Co v Iran (1982) 70 ILR 490, 492.

137  Lauterpacht, ILC Ybk 1953/II, 153; Fitzmaurice (1953) 2 ICLQ 25, 35–7; Waldock, ILC Ybk 1963/II, 48–50; Oraison, L’Erreur dans les traités (1972); Thirlway (1992) 63 BY 1, 22–8; Villiger, Commentary (2009) 603–12.

138  Also: ILC Ybk 1966/II, 243–4.

139  Temple, ICJ Reports 1962 p 6, 26–7; ibid, 57–9 (Judge Fitzmaurice).

140  Lauterpacht, ILC Ybk 1953/II, 152; Fitzmaurice, ILC Ybk 1958/II, 25, 37; Waldock, ILC Ybk 1963/II, 47–8; Oraison (1975) 75 RGDIP 617; Villiger, Commentary (2009) 613–22.

141  VCLT, Art 49. See ILC Final Report and Draft Articles, ILC Ybk 1966/II, 244–5.

142  ILC Ybk 1966/II, 245.

143  Villiger, Commentary (2009) 621–8; Corten & Klein (2011) 1169–78.

144  Fitzmaurice, ILC Ybk 1958/II, 26, 38; Waldock, ILC Ybk 1963/II, 36, 50; ILC Final Report and Draft Articles, ILC Ybk 1966/II, 245–6 (Art 48); de Jong (1984) 15 NYIL 209; Villiger, Commentary (2009) 629–37.

145  Draft Articles, II, ILC Ybk 1963/II, 197–8 (Art 36); Waldock, ILC Ybk 1963/II, 51–2; Lauterpacht, ILC Ybk 1953/II, 147–52; McNair (1961) 206–11; Brownlie, Use of Force (1963) 404–6; Fitzmaurice, ILC Ybk 1957/II, 32, 56–7; Fitzmaurice, ILC Ybk 1958/II, 26, 38–9; de Jong (1984) 15 NYIL 209; Caflisch (1992) 35 GYIL 52. Also: Fisheries Jurisdiction (UK v Iceland), Jurisdiction, ICJ Reports 1973 p 3, 14; Thirlway (1992) 63 BY 1, 28–31.

146  Also: ILC Final Report and Draft Articles, ILC Ybk 1966/II, 246–7 (Art 49); Kearney & Dalton (1970) 64 AJIL 495, 532; de Jong (1984) 15 NYIL 209; Villiger, Commentary (2009) 638–50; Corten & Klein (2011) 1201–23.

147  A/CONF.39/26, 23 May 1969, 285.

148  De Visscher (1971) 75 RGDIP 5; Gaja (1981) 172 Hague Recueil 271; D’Amato (1990) 6 Conn JIL 1; Charney (1993) 87 AJIL 529; Kolb, Théorie du Jus Cogens International (2001); Kolb (2005) 109 RGDIP 305; Tomuschat & Thouvein (eds), The Fundamental Rules of the International Legal Order (2006) 83; Orakhelashvili, Peremptory Norms in International Law (2006).

149  ILC Final Report and Draft Articles, ILC Ybk 1966/II, 247–9 (Art 50); Gaja (1981) 172 Hague Recueil 271, 279–89; Villiger, Commentary (2009) 661–78; Corten & Klein (2011) 1224–35.

150  VCLT, Art 64. See Fitzmaurice, ILC Ybk 1957/II, 29–30, 51; Draft Articles, II, ILC Ybk 1963/II, 211 (Art 45); Waldock, ILC Ybk 1963/II, 77, 79; ILC Final Report and Draft Articles, ILC Ybk 1966/II, 261 (Art 61); Villiger (2009) 344 Hague Recueil 9, 135–41.

151  Villiger (2009) 344 Hague Recueil 9, 137.

152  E.g. Gaja (1981) 172 Hague Recueil 271, 279; cf Villiger (2009) 344 Hague Recueil 9, 140–1.

153  E.g Aust (2nd edn, 2007) 277–311; Corten & Klein (2011) 1236–454.

154  If it is a bilateral treaty, denunciation by one party will terminate it; if it is multilateral, the withdrawal of the denouncing party will usually not terminate the whole treaty. Treaties may also be terminated at any time by the consent of all the parties, after consultation. See VCLT, Art 54; ILC Final Report and Draft Articles, ILC Ybk 1966/II, 249 (Art 51); Briggs (1974) 68 AJIL 51; Helfer (2005) 91 Va LR 1579; Aust (2nd edn, 2007) 277.

155  VCLT, Art 56; Fitzmaurice, ILC Ybk 1957/II, 22; Draft Articles, II, ILC Ybk 1963/II, 200–1 (Art 39); Waldock, ILC Ybk 1963/II, 63–70; ILC Final Report and Draft Articles, ILC Ybk 1966/II, 250–1 (Art 53); Jiménez de Aréchaga (1978) 159 Hague Recueil 1, 70–1; Widdows (1982) 53 BY 83; Sinclair (2nd edn, 1984) 186–8; Plender (1986) 57 BY 133, 143; Villiger, Commentary (2009) 695–706. See also Interpretation of the Agreement of 25 March 1951 between the WHO and Egypt, ICJ Reports 1980 p 73, 94–6, 128–9 (Judge Mosler), 159–62 (Judge Ago), 176–7 (Judge El-Erian), 184–9 (Judge Sette-Camara); Nicaragua, Jurisdiction and Admissibility, ICJ Reports 1984 p 392, 419–20.

156  McNair (1961) ch 43; Broms (1981/I) 59 Ann de l’Inst 201; Chinkin (1981) 7 Yale JWPO 177; Delbrück (2000) 4 EPIL 1367.

157  IDI Res, Helsinki/III (1985); Greenwood (1987) 36 ICLQ 283, 296–7.

158  Masinimport v Scottish Mechanical Light Industries (1976) 74 ILR 559, 564.

159  ILC Ybk 1963/II, 187, 189.

160  See www.untreaty.un.org/ilc/summaries/1_10.htm. Brownlie was appointed Special Rapporteur; he was succeeded by Caflisch in 2009.

161  ILC Report 2011, GAOR, 66th Session, Supp No 10, A/66/10, 173–217. Further: Bannelier, in Angelet, Corten & Klein (eds), Droit du Pouvoir, Pouvoir du Droit (2007) 125.

162  VCLT, Art 54; Draft Articles, II, ILC Ybk 1963/II, 203–4 (Art 40); ILC Final Report and Draft Articles, ILC Ybk 1966/II, 251–2 (Art 54). Also: Kontou (1994).

163  VCLT, Art 59; Draft Articles, II, ILC Ybk 1963/II, 203–4 (Art 41); ILC Final Report and Draft Articles, ILC Ybk 1966/II, 252–3 (Art 56); Plender (1986) 57 BY 133, 153–7. Also: Electricity Company of Sofia and Bulgaria (1939) PCIJ Ser A/B No 77, 92 (Judge Anzilotti).

164  Fitzmaurice, ILC Ybk 1957/II, 28, 47–8, 52; ILC Final Report and Draft Articles, ILC Ybk 1966/II, 237; Thirlway (1992) 63 BY 1, 94–6; Kohen, in Cannizzaro (2011) 350. Also: Widjatmiko v Gebroeders Zomer en Keunig’s Drukkerij Vada, Uitgeversmij (1971) 70 ILR 439; Nuclear Tests (Australia v France), ICJ Reports 1974 p 253, 337–8 (Judges Onyeama, Dillard, Jiménez de Aréchaga & Sir Humphrey Waldock, diss), 381 (Judge de Castro, diss), 404, 415–16 (Judge Barwick, diss).

165  McNair (1961) ch 36; Simma, (1970) 20 ÖZföR 5; Rosenne, Breach of Treaty (1985); Hutchinson (1988) 58 BY 151; Kirgis (1989) 22 Cornell ILJ 549; Kontou (1994); Gomaa, Suspension and Termination of Treaties on Grounds of Breach (1996); Fitzmaurice (2001) 6 Austrian RIEL 3; Laly-Chevalier, La Violation du traité (2005); Villiger (2009) 344 Hague Recueil 9, 144–59; Corten & Klein (2011) 1350–81.

166  The Court rejected Hungary’s argument: ICJ Reports 1997 p 7, 60–2, 65–7. Of course it makes a difference under Art 60 which party is trying to get rid of the treaty. In Rainbow Warrior the tribunal held that France had committed a material breach of the agreement in question but ultimately this finding was of little practical consequence: see (1990) 82 ILR 499.

167  Also: Draft Articles, II, ILC Ybk 1963/II, 204–6 (Art 42); Waldock, ILC Ybk 1963/II, 72–7; ILC Final Report and Draft Articles, ILC Ybk 1966/II, 253–5 (Art 57).

168  E.g. Simma (1970) 20 ÖZföR 5; Klabbers, in Tupamäki (ed), Essays on International Law (1998) 20; Fitzmaurice (2001) 6 Austrian RIEL 3.

169  This definition was applied by analogy in Namibia, ICJ Reports 1971 p 16, 46–7, in respect of South African violations of the Mandate for South West Africa (Namibia) and the consequent revocation of the Mandate by the UN General Assembly.

170  For comment: Simma (1970) 20 ÖZföR 5, 61.

171  Gabčíkovo-Nagymaros, ICJ Reports 1997 p 7, 65–7.

172  Sinclair (2nd edn, 1984) 190–2; Aust (2nd edn, 2007) 296; Villiger, Commentary (2009) 752–61.

173  VCLT, Art 61(1); Draft Articles, II, ILC Ybk 1963/II, 206 (Art 43); ILC Final Report and Draft Articles, ILC Ybk 1966/II, 255–6 (Art 58). Another example of impossibility arises from the extinction of one of the parties to a bilateral treaty, apart from any rule of state succession which might allow devolution: Waldock, ILC Ybk 1963/II, 77–9. For succession see chapter 18.

174  Gabčíkovo-Nagymaros, ICJ Reports 1997 p 7, 63–4.

175  Draft Articles, II, ILC Ybk 1963/II, 207–11 (Art 44); Waldock, ILC Ybk 1963/II, 79–85; ILC Final Report and Draft Articles, ILC Ybk 1966/II, 256–60 (Art 59); van Bogaert (1966) 70 RGDIP 49; Lissitzyn (1967) 61 AJIL 895; Schwelb (1969) 29 ZaöRV 39; Haraszti (1975) 146 Hague Recueil 1; Cahier, in Lamberti Zanardi et al (eds), Essays in Honour of Roberto Ago (1987) 163; Thirlway (1992) 63 BY 1, 75–82.

176  (1932) PCIJ Ser A/B No 46, 156–8; the Court observed that the facts did not justify the application of the doctrine, which had been invoked by France.

177  Jurisdiction, ICJ Reports 1973 p 3, 20–1. Also: Fisheries Jurisdiction (Germany v Iceland), Jurisdiction, ICJ Reports 1973 p 49; and Briggs (1974) 68 AJIL 51.

178  Gabčíkovo-Nagymaros, ICJ Reports 1997 p 7, 65.

179  Ibid.

180  (1998) 117 ILR 399.

181  Ibid, 442. The issue was not addressed in much depth, however, as the Court approached it as a matter of judicial review: see Aust (2nd edn, 2007) 299. For criticism of Racke: Klabbers (1999) 36 CMLR 179.

182  VCLT, Art 73. In its work on the law of treaties the ILC put this question aside: ILC Final Report and Draft Articles, ILC Ybk 1966/II, 267–8 (Art 69). See also chapter 19.

183  See VCLT, Part V, Sections 3–4. Further: Cahier (1972) 76 RGDIP 645, 672–89; Villiger, Commentary (2009) 799–891; Corten & Klein (2011) 1455–62.

184  Procedure: Arts 65–8. Further: Briggs (1967) 61 AJIL 976; Morelli (1974) 57 RDI 5; David, The Strategy of Termination (1976); Thirlway (1992) 63 BY 1, 85; Villiger (2009) 344 Hague Recueil 9, 160–82.

185  ILC Ybk 1966/II, 238–9, 261. For comment: Sinclair (1970) 19 ICLQ 67.