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Oppenheim's International Law - Volume 1 Peace, 9th Edition edited by Jennings, Robert; Watts KCMG QC, Arthur (19th June 2008)

Part 4 International transactions, Ch.14 Treaties, Character and Function of Treaties

Sir Robert Jennings qc, Sir Arthur Watts kcmg qc

From: Oppenheim's International Law: Volume 1 Peace (9th Edition)

Edited By: Robert Jennings, Arthur Watts KCMG QC

From: Oxford Public International Law (http://opil.ouplaw.com). (c) Oxford University Press, 2015. All Rights Reserved. Subscriber: null; date: 20 August 2019

Vienna Convention on the Law of Treaties — Treaties, binding force

Character and Function of Treaties

Harv Research (1935), pt III, pp 686–705 Dupuis, Hag R (1924), i, pp 322–49 Butler and Maccoby, The Development of International Law (1928), ch xvii Hoijer, Les Traités internationaux, 2 vols, (1928) Chailley, La Nature juridique des traités internationaux (1932), pp 3–72 Frangulis, Théorie et pratique des traités internationaux (1936) Jessup, A Modern Law of Nations (1948), pp 123–56 Pillaut, Clunet, 46 (1919), pp 593–602 Réglade, Revue de droit public et de la science politique, 41 (1924), pp 505–40 Crocker, AJ, 18 (1924), pp 38–55 Report by Mastny and Rundstein for League Codification Committee, AJ, 20 (1926), Special Suppl pp 204–21 McNair, BY, 11 (1930), pp 100–118 Whitton, Hag R, 49 (1934), iii, pp 175–249 Kraus, ibid, 50 (1934), iv, pp 317–96 Kelsen, Théorie du droit, 10 (1936), pp 253–92 Mann, BY, 21 (1944), pp 11–33 Kunz, AJ, 39 (1945), pp 180–97 Starke, BY, 23 (1946), pp 341–6 Jessup, AJ, 41 (1947), pp 378–405 Fawcett, BY, 30 (1953), pp 381–400 Fitzmaurice, BY, 35 (1959), pp 194–6 Wehberg, AJ, 53 (1959), pp 775–86, and Festschrift für Alfred Verdross (1960), pp 307–19 de Arechaga, Hag R, 159 (1978), i, pp 35–7 Widdows, BY, 50 (1979), pp 117–50 Satow, pp 236–63 Parry, in Multum non Multa (Festschrift für Lipstein) (eds Fuerstein and Parry, 1980), pp 221–39 Sinclair, The Vienna Convention on the Law of Treaties (2nd ed, 1984), pp 1–28 Restatement (Third), i, pp 149–52 Reuter, Introduction to the Law of Treaties (Eng trans, 1989, by Mico and Haggenmacher, of 2nd ed (1985) of original in French) Igweike, Indian JIL, 28 (1988), pp 249–63. And see bibliography preceding § 8, and § 11, as to treaties as a source of international law.

§ 581  Development of the law of treaties: Vienna Conventions on the Law of Treaties 1969 and 1986

Treaties, being essentially written agreements between states, have had a prominent place in international relations since long before international law in the modern sense of the term was in existence.1 The customary rules of international law relating to treaties gradually acquired considerable certainty and precision. Nevertheless, the very great importance of treaties in international relations and the uncertainty or unsatisfactoriness of some aspects of customary international law made the law of treaties a suitable (p. 1198) subject for consideration by the International Law Commission.2 In 1966, the Commission adopted its final report on the law of treaties, containing a set of draft Articles and commentaries upon them.3 These served as the basic proposal before a Conference, attended by representatives of over 100 states,4 which was held in Vienna in two sessions, in 1968 and 1969, and adopted the Vienna Convention on the Law of Treaties.5 The Convention entered into force on 27 January 1980.

In 1986 a further Convention was concluded, also in Vienna and also on the basis of preparatory work by the International Law Commission,6 on the Law of Treaties between States and International Organizations or between International Organisations7 This Convention has the broad effect of applying to international agreements between such parties the designation of ‘treaties’, and extending to them substantially the same rules, mutatis mutandis, as apply to treaties between states under the Vienna Convention of 1969. Accordingly, it is that Convention whose provisions will principally be considered, particularly since the 1986 Convention may not enter into force for some time yet.

The Vienna Convention of 1969 deals with the greater part of the law of treaties. The customary law of treaties is nevertheless still relevant for questions not regulated by the provisions of the Vienna Convention;8 for international agreements not within the scope of the Convention;9 for treaties concluded by (p. 1199) states before the entry into force of the Convention with regard to such states;10 and for treaties involving states not parties to the Convention.11 One further general limitation upon the application of the Convention which should be noted concerns treaties which are constituent instruments of, or which are adopted within, international organisations: the Convention applies to such treaties without prejudice to any relevant rules of the organisation.12 In the following pages, therefore, while primary consideration will be given to the law as it is under the Vienna Convention of 1969, the applicable rules of customary international law will also be considered. It must be noted that many provisions of the Vienna Convention reflect rules of customary international law which are binding as such quite apart from the Convention;13 and that other provisions of the Convention may themselves be expected in time to acquire the force of rules of customary law.14

§ 582  Concept of treaties

The Vienna Convention defines ‘treaty’ as ‘an international agreement concluded between States1 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’.2 This definition involves no fundamental departure from customary international law,3 although several points in the definition require emphasis.

  1. (1)  ‘Treaty’ is given a generic meaning, rather than a meaning limited to one particular form of international agreement.4

  2. (p. 1200) (2)  Whether or not an instrument constitutes a treaty does not depend on its designation.5

  3. (3)  The fact that the definition, like the Convention as a whole, only applies to agreements between states, does not affect the legal force of agreements between states and other subjects of international law or between such other subjects, or the application to such agreements of any of the rules in the Convention to which they would be subject under international law independently of the Convention, or the application of the Convention to the relations to states as between themselves under international agreements to which other subjects of international law are also parties.6

  4. (4)  The agreement must be governed by international law. So agreements subject to some national system of law will not constitute treaties, even though the parties are states, or, perhaps more usually in these circumstances, government departments of different states.7 Where the agreement is concluded between parties who have no international legal personality it will not be governed by international law.8

  5. (5)  In addition to the traditional form of treaties — ie treaties negotiated and signed expressly on behalf of the Head of State by virtue of full powers received from him — treaties may be concluded between governments or between departments of governments.9 The former, concluded between (p. 1201) the governments of the contracting parties, are, in their legal effect, in the same category as ordinary treaties concluded on behalf of the state. They are not limited to matters of minor or transient importance. The main reason for adopting this form of treaty is that it is attended by less formality and that, occasionally, it obviates certain inconveniences connected with the internal law of the country concerned.10

    However that may be, the international validity of such agreements is the same as that of ordinary treaties. The same applies to agreements made, with the authority of the governments concerned, between government departments or ministries.11 Often treaties provide expressly for interdepartmental arrangements of this nature.12

  6. (6)  Although the agreement must be in written form in order to come within the scope of the Convention, this does not affect the legal force of oral agreements.13

  7. (7)  The definition does not assist very much with the answer to the question whether a particular instrument is ‘an international agreement … governed (p. 1202) by international law’. It is suggested that the decisive factor is still14 whether the instrument is intended to create international legal rights and obligations between the parties — an element which the International Law Commission regarded as embraced within the phrase ‘governed by international law’.15 The existence or otherwise of such an intention will need to be determined in the light of all the circumstances of each case. The registration of an instrument with the United Nations may imply that it was intended and understood to be a treaty.16 In some cases, as with the Universal Declaration of Human Rights,17 the absence of an intention to undertake a legal obligation appears clearly from the statements made by governments prior to the adoption of the text of the instrument. In other cases the clauses of the instrument indicate with sufficient clarity that they are intended as formulating general statements of principle and policy rather than legal obligations.18 A difficult question arises in cases in which the terms of the undertaking leave to the parties a measure of discretion so wide as to raise doubts whether there exists a legal obligation.19 In such cases, it is believed, the determination of the extent of the obligation of a state, although lying within the competence of the interested state, must take place in accordance with the legal duty to act in good faith. The fact that the interested state is the judge of the existence of the obligation is, although otherwise of considerable importance, not of decisive relevance for the determination of the legal character of the instrument.20 Where states wish to record certain matters in writing, but wish to do so in a manner which is not intended to create legal rights and obligations and (p. 1203) does not constitute a legally binding agreement, various procedures are open to them.21 Thus they may conclude a memorandum of understanding,22 or they may make parallel — but unilateral rather than consensual statements,23 or they may record their views in a ‘gentleman’s agreement’ thereby implying that they do not have the intention of entering upon legal rights or obligations,24 or they may adopt a Declaration intended as more a statement of policy and intention than a legally binding instrument.25 Although the designations given to these various procedures may be indicative of their non-binding character, the decisive element in any particular case is the intention of the parties.

§ 583  So-called law-making treaties

Attempts at classification of the different kinds of treaties1 are of limited usefulness. Nevertheless, one distinction which has practical consequences is that between bilateral and multilateral treaties. While the underlying legal principles of treaty law apply to multilateral treaties as to bilateral treaties, the existence of numerous parties to the former give rise to particular problems as regards the legal relations between parties in such matters as conclusion and entry into force of such treaties, reservations to them, their interpretation, withdrawal from them and their termination.2

(p. 1204) A further distinction which, although controversial and theoretically faulty, is nevertheless of some practical importance is that between treaties concluded for the purpose of laying down general rules of conduct among a considerable number of states (which may be termed ‘law-making’ treaties)3 and treaties concluded for any other purpose. In a sense the distinction between law-making and other treaties is merely one of convenience. In principle, all treaties are law-making inasmuch as they lay down rules of conduct which the parties are bound to observe as law. However, relatively extensive participation4 in a treaty, coupled with a subject matter of general significance and stipulations which accord with the general sense of the international community, do establish for some treaties an influence far beyond the limits of formal participation in them. These factors give such a treaty something of the complexion of a legislative instrument, and assist the acceptance of the treaty’s provisions as customary international law in addition to their contractual value for the parties.5 No fixed (p. 1205) time can be set for the evolution of such treaty rules into rules of customary international law. The process whereby a treaty’s provisions may come also to be rules of customary law is of considerable significance for the role of treaties in international law.6

In addition, judicial practice has tended to recognise a type of treaty which, although contractual in origin and character, possesses an existence independent of and transcending the parties to the treaty. Thus in the case concerning the Status of South West Africa the International Court of Justice held that the provisions of the Mandate for South West Africa — which was in the nature of a treaty between the Council of the League of Nations and South Africa — were not decisively affected by the fact that the League had ceased to exist. ‘The international rules regulating the Mandate constituted an international status for the Territory recognised by all the Members of the League of Nations, including the Union of South Africa.’7 Similarly, the effect of establishing a status or regime valid erga omnes8 has on occasion been attributed to treaties establishing a new state9 or an international organisation,10 to treaties imposing a special status upon a territory,11 and to treaties creating a special regime for an international (p. 1206) waterway.12 It is not settled whether treaties in this category are juridically similar to other law-making treaties in that their extra-contractual effects are based on the operation of their provisions as customary law following the general consent of other states, whether they have some inherent and distinct juridical element of their own, or whether they merely illustrate a particular application of the normal rules governing the acquisition by third states of rights and obligations under treaties.13

§ 584  Binding force of treaties

Article 26 of the Vienna Convention on the Law of Treaties provides: ‘Every treaty in force1 is binding upon the parties to it and must be performed by them in good faith’.2 The question why international treaties have binding force has been much disputed.3 The correct answer is probably that treaties are legally binding, because there exists a customary rule of international law that treaties are binding. The binding effect of that rule rests in the last resort on the fundamental assumption, which is neither consensual nor necessarlly legal, of the objectively binding force of international law.4


For the predominance of treaties, as compared with customary international law, in medieval practice, see Schwarzenberger, BY, 25 (1948), pp 87–90. See also Ténékidès, Hag R, 90 (1956), pp 518–32 as to the operation of treaties in the Greek city states in the 3rd, 4th and 5th centuries BC. As to the role of the oath in ancient treaties, see Magnetti, AJ, 72 (1978), pp 815–29.

At its first session in 1949 the Commission included the law of treaties in its provisional list of topics selected for codification. See § 30. The League of Nations Committee set up in 1924 to report on the codification of international law did not include the substantive law of treaties as ripe for codification (see § 29); the Pan-American Conference adopted a codifying Convention on Treaties in 1928 (AJ, 22 (1928), Suppl, p 124ff).

YBILC (1966), ii, pp 173–274. The ILC’s Commentaries are an invaluable source of reference. The UN Secretariat prepared in 1967 a valuable Guide to the Draft Articles on the Law of Treaties Adopted by the International Law Commission at its Eighteenth Session (1966), giving references to previous consideration in the UN and by the ILC to each of the final draft Articles: UN Doc A/C 6/376. See also, for comment on the ILC’s final draft Articles, a series of contributions in ZöV, 27 (1967), pp 408–561; and Lachs, Recueil d’études de droit international en hommage à Paul Guggenheim (1968), pp 391–402.

103 states attended the first session of the Conference, and 110 the second. For a summary of the background to the convening of the Conference, see Sinclair, ICLQ, 19 (1970), pp 50–53. On the conference itself see Nahlik, AFDI, 15 (1969), pp 24–53; Daudet, ibid, pp 54–69; Rosenne, Developments in the Law of Treaties 1945–1986 (1989), pp 364–90.

AJ, 63 (1969), p 875; TS No 58 (1980); ILM, 8 (1969), p 679. See generally on the Convention, Nahlik, AFDI, 15 (1969), pp 24–53; Kearney and Dalton, AJ, 64 (1970), pp 495–561; de la Guardia and Delpech, El Derecho de los Tratados y la Convención de Viena de 1969 (1970); Rosenne, The Law of Treaties (1970); (with a valuable account of the legislative history of each article; and see Briggs, AJ, 65 (1971), pp 705–12), and Transnational Law in a Changing Society (ed Friedmann, Henkin and Lissitzyn, 1972), pp 202–27; Nascimento e Silva, Conferencia de Viena sobre o Direito dos Tratados (1971); Ago, Hag R, 134 (1971), iii, pp 297–332; Elias, The Modern Law of Treaties (1974); Wetzel, The Vienna Convention on the Law of Treaties (1978); Sinclair, The Vienna Convention on the Law of Treaties (2nd ed, 1984), and AS Proceedings (1984), pp 271–5; Dalton, ibid, pp 276–9.

YBILC (1982), ii, pt 2, pp 9–77.

ILM, 25 (1986), p 543. See generally § 596.

Preamble to the Vienna Convention.

Articles 1 and 3: these agreements are those concluded between states and other subjects of international law or between such other subjects, and agreements not in written form. See also the Resolution relating to Art 1 of the Convention adopted by the Conference. However, see, as to the law relating to treaties between states and international organisations, or between two such organisations, n 7.

10  Article 4. See McDade, ICLQ, 35 (1986), pp 499–511; and § 11, n 16.

11  On which see Vierdag, AJ, 76 (1982), pp 779–801.

12  A similar provision is included in Art 5 of the Vienna Convention of 1986. And see § 629, n 4.

13  See Sinclair, ICLQ, 19 (1970), pp 49–50; Briggs, AJ, 73 (1979), pp 470–73.

14  See § 583.

As to international agreements to which one or more international organisations are parties, see the Convention on the Law of Treaties between States and International Organisations or between International Organisations 1986 (ILM, 25 (1986), p 543): Article 2.1(a) defines such agreements as ‘treaties’ in terms modelled on those of the definition in the Vienna Convention of 1969. See § 595 as to agreements with less than fully sovereign states.

Article 2(1)(a). ‘While the concept of “treaty” used in the Convention is restricted in its scope, certain of the provisions of the Convention have analogous application to international agreements in general which are governed by international law’: BP Exploration Co (Libya) Ltd v Government of the Libyan Arab Republic (1974), ILR, 53, pp 297, 332 (said in relation to a concession agreement).

As to the meaning of the terms ‘treaty’ and ‘agreement’ for purposes of Art 102 of the Charter, see § 663, n 1.

Volume I of 8th ed of this work stated that ‘International treaties are agreements, of a contractual character, between States, or organisations of States, creating legal rights and obligations between the parties’ (p 877). See also F A Mann, BY, 33 (1957), at pp 30–33; Barberis, AFDI, 30 (1984), pp 239, 248–60.

See ILC Commentary (Treaties), Art 2, paras (2)–(4): YBILC (1966), ii, p 187. Whether an instrument constitutes an international agreement may, for purposes of municipal law, be a matter for determination by the executive branch of government: see Maison Moraly and Société Moraly (1969), ILR, 52, p 406.

See § 586.

Article 3(b) and (c). Thus the definition is not inconsistent with the decision of the ICJ in the South West Africa Cases that ‘the Mandate, in fact and in law, is an international agreement having the character of a treaty or convention’ (ICJ Rep (1962), p 330; see also the Namibia (Legal Consequences) Advisory Opinion, ICJ Rep (1971), pp 46–7), or its acceptance of a similar characterisation of Trusteeship Agreements by both parties in the Northern Cameroons Case (ICJ Rep (1963), p 15): but note the joint Dissenting Opinion of Judges Spender and Fitzmaurice in the former case, at pp 473–503. In the Anglo-Iranian Oil Co Case the UK argued that a concession agreement between the company and the Iranian Government partook of a treaty character because of the circumstances of its conclusion (involving the League of Nations): the ICJ rejected this argument (ICJ Rep (1952), at p 112). For comment on the issues involved, see Fitzmaurice, BY, 33 (1957), pp 238–50; and see generally, § 12, n 12, and § 408, as to concession agreements, and other agreements between states and private parties.

See also the Vienna Convention of 1986 referred to at n 1, as regards treaties concluded by international organisations.

For discussion of a somewhat unusual decision of the Federal German Supreme Court holding an international agreement to be subject to municipal law, see F A Mann, AJ, 68 (1974), pp 490–96. States may, of course, intend to conclude agreements subject to municipal law, but these will be more in the nature of private law contracts than international treaties. See F A Mann, BY, 21 (1944), pp 11–33; BY, 35 (1959), pp 34–57; and Studies in International Law (1973), pp 241–55 (in which volume, at pp 179–210 and 211–40, both previous articles are reprinted). And see ICLQ, 10 (1961), pp 575–6.

As to agreements between states and private parties, particularly private corporations, see § 12, n 12.

For its administrative purposes connected with the registration of treaties the UN Secretariat does not regard agreements between the UN and non-sovereign bodies as treaties, nor agreements between states and certain organisations which lack treaty-making capacity. As to agreements between states and dependent territories see § 84, n 14ff. The Allied occupation authorities in Europe after the Second World War were held not to have the character of a foreign state, with the result that an agreement concluded between the Allied High Commission and the (West) German Government was held not to constitute a treaty with a foreign state, although it ‘partakes of International Law’: Petersberg Agreement Case, ILR, 19 (1952), No 95. See also OMA v Koerperich, ILR, 18 (1951), No 117.

For a detailed discussion of the subject see M Jones, BY, 21 (1944), pp 111–22. It will be noted that the opening passage of the Preamble to the Charter of the United Nations is: ‘We, the peoples of the United Nations …’ The Preamble to the Constitution of the Food and Agriculture Organisation of the United Nations begins: ‘The Nations accepting this Constitution …’

In Loschetter v Public Prosecutor (1960), ILR, 31, p 425, a Protocol signed by Ministers of Agriculture was held to be still a valid international agreement even though the constitution of the state concerned required treaties to be signed by the Head of State; in United States of America v Novick (1960), ILR, 32, p 275, a treaty concluded in the name of ‘Canada’ was held to have been validly concluded notwithstanding that the relevant national law referred to treaties concluded by ‘Her Majesty’. Cf Re Chatelain (1965), ILR, 47, p 113, denying the status of an international agreement to an agreement signed by the heads of two states’ fisheries services.

10  See, eg as to the use by the USA of ‘executive agreements’ in a sense different from ‘treaty’ as used in the Constitution, § 19, n 95, and in particular the judgment of the Supreme Court in Weinberger v Rossi, ILM, 21 (1982), p 660. See also extracts from the Congressional Record (9 October 1975), and the position of the State Department Legal Adviser (6 October 1975), on various US-Israel arrangements concluded in 1975: ILM, 14 (1975), pp 1585–96.

For a time some of the British Dominions attached importance to being able to conclude treaties without resorting to the somewhat cumbrous procedure of receiving authority for the issue of Full Powers under the Great Seal: see § 78, n 8.

11  See, eg the Agreement concerning Telecommunications concluded on 15 December 1936, between the Telegraph Administrations of Denmark, Finland, Iceland, Norway, and Sweden: Hudson, Legislation, vii, p 492; or the Agreement between the post office authorities of those countries of 31 December 1934, concerning postal exchanges: ibid, vi, p 365. However, for an agreement between the Postmaster-General of the UK, the Danish General Directorate of Posts and Telegraphs, the Icelandic General Directorate of Posts and Telegraphs and the Great Northern Telegraph Company Ltd, see comment in ICLQ, 10 (1961), p 575, but note Williams v Blount (1970), ILR, 56, p 234, treating the Universal Postal Convention as only having the effect of an administrative regulation (at p 240), but semble within the framework of US law rather than international law. For purposes of national law an agreement between the heads of the French and Swiss fisheries services has been held not to constitute a treaty, as has an agreement between the ministries of justice of the Federal Republic of Germany and Austria: Re Chatelain (1965), ILR, 47, p 113; Prosecution for Misdemeanours (Germany) Case, ILR, 22 (1955), p 560. In the case of interdepartmental agreements it is essential, if they are to be regarded as treaties, that their effect should be to bind the states concerned.

12  See, eg an Agreement cited by M Jones, BY, 21 (1944), p 119, n 4, between the British Air Ministry and the Austrian Federal Ministry of Commerce, based on Art 1, para 2 of the Air Navigation Convention concluded between the two countries in 1933.

13  Article 3; see YBILC (1982), ii, pt 2, p 22, para (2). See also §§ 459, n 4, 577 and 585, n 2. In United States v Gonzalez, AJ, 80 (1986), p 653, a conversation by telephone was held to constitute an ‘arrangement’ with another government.

14  See vol I of 8th ed of this work, § 508a. See also Fawcett, BY, 30 (1953), pp 381–400.

15  See ILC Commentary (Treaties), Art 2, para (6): YBILC (1966), ii, p 189.

16  South West Africa Cases (Preliminary Objections), ICJ Rep (1962), at pp 331–2. A contrario, non-registration may be taken to indicate an intention to enter into only a non-binding engagement, or as supporting statements to that effect: see the Joint Dissenting Opinion of Judges Spender and Fitzmaurice, ibid, p 503.

17  See § 437.

18  See, eg Fawcett in YB of World Affairs (1951), pp 286–9, with regard to the Havana Charter of the International Trade Organisation of 1948 and Mann, BY, 26 (1949), pp 264–5 with regard to certain declarations of monetary policy. As to declarations in general, see § 577. Two acts, in themselves unilateral, may taken together establish a consensual relationship, as with Declarations accepting the ‘optional’ clause for the jurisdiction of the ICJ: see Rights of Passage Case (Preliminary Objections), ICJ Rep (1957), at pp 145–7.

A growing practice is to adopt international ‘Codes of Conduct’ on various matters, such as the ‘Guidelines for Multinational Enterprises’ adopted by the OECD in 1976 (ILM, 15 (1976), p 297), and the Code of Conduct for Liner Conferences 1974 (but note that this Code was embodied in a convention): see Odier, AFDI, 25 (1979), pp 686–92. A UN Code of Conduct for Transnational Corporations has been under discussion for a number of years, and ‘substantial provisional understanding on [its] contents’ has been reached (GA Res 45/186 (1990)): see on this draft Code Francioni, Ital YBIL, 3 (1977), pp 143–70; Spröte, Germ YBIL, 33 (1990), pp 331–48. On these and other codes and on the general question of the voluntary or binding nature of such codes, see Coonrod, Harv ILJ, 18 (1977), pp 273–307; Jeffries, ibid, pp 309–42; Schwartz, International Lawyer, 11 (1977), pp 529–36; Davidow and Chiles, AJ, 72 (1978), pp 247–71; Decaux, AFDI, 29 (1983), pp 81–97. And see § 380, n 15.

19  As to certain Declarations accepting the compulsory jurisdiction of the ICJ, see § 577, nn 21–4.

20  The same applies to treaties such as the North Atlantic Treaty of 4 April 1949 (see § 665), in which each party agrees to assist others by ‘such action as it deems necessary’.

21  The ICJ has noted that, for the creation of legal relations, the principal emphasis is placed on the intentions of the states concerned, given that ‘the question of form … is not a domain in which international law imposes any special or strict requirements’: Nuclear Tests Case, ICJ Rep (1974), pp 267–8; see also the Temple of Preah Vihear Case, ICJ Rep (1961), pp 31–2.

See generally Münch, ZöV, 29 (1969), pp 1–11; Schachter, AJ, 71 (1977), pp 296–304, and Hag R, 178 (1982), v, pp 123–32; Virally, Annuaire, 60 (1) (1983), pp 166–257, 328–57; Tunkin, Law and Force in the International System (1985), pp 129–44; Aust, ICLQ, 35 (1986), pp 787–812; Mullerson, AJ, 83 (1989), pp 509–12; Rosenne, Developments in the Law of Treaties 1945–1986 (1989), pp 85–123; and see § 586, n 8.

22  See § 586, n 8.

23  See, eg Cohen, AS Proceedings, 66 (1972), pp 110–11.

24  See Eisemann, Clunet, 106 (1979), pp 326–48. Examples of ‘gentleman’s agreements’ are that which formed the basis for scientific cooperation in Antarctica during the International Geophysical Year 1957–58 without prejudicing disputed questions of sovereignty (see Auburn, Antarctic Law and Politics (1982), pp 89–93); and that which recorded certain voting arrangements to apply during the UN Law of the Sea Conference (see § 575, n 13).

As to the possible emergence of the ‘package deal’ as an informal form for reaching agreements see Caminos and Molitor, AJ, 79 (1985), pp 871–90, with particular reference to the work of the UN Conference on the Law of the Sea.

25  See § 577.

See Heffter, §§ 89–91; Bluntschli, §§ 442–5; Martens, i, § 113; Ullmann, § 82; Wheaton, § 268 (following Vattel, ii, § 169); Rivier, ii, pp 106–18; Westlake, i, p 294; Hatschek, p 228; Rapisardi-Mirabelli, RI, 3rd series, 4 (1923), pp 653–67; McNair, BY, 11 (1930), pp 100–18; de Caviedes, Hag R, 118 (1966), ii, pp 117–27; Dehaussy, Recueil d’études de droit international en hommage à Paul Guggenheim (1968), pp 305–26; and many others.

The particular problems to which multilateral treaties give rise in these various respects are dealt with in the appropriate paragraphs in the following pages. See generally as to multilateral treaties Lachs, Hag R, 92 (1957), ii, pp 236–333; Sprudzs, AJ, 66 (1972), pp 365–76. Note also the work done in the Sixth Committee of the UN General Assembly on the Multilateral treaty-making process, particularly the Report of the Secretary-General (A/35/312, and Corr 1 (1980)), the views of governments and the ILC (ibid, addenda 1 and 2), further Reports by the Secretary-General (A/36/553 and A/37/44 (1981, 1982)), the Report of the Working Group established by the Sixth Committee (A/C 6/39/L12, Annex), and GA Res 39/90 (1984). See also Review of the Multilateral Treaty-Making Process (UN Legislative Series, ST/LEG/SERIES B/21 (1985)); Rosenne, Developments in the Law of Treaties 1945–1986 (1989), pp 390–8.

See also §§ 11, n 9; § 16 (as to ‘law-making’ powers of international organisations); and § 32 (as to the revision of international law). In so far as the expression ‘law-making treaties’ is used as synonymous with ‘international legislation’ it must be remembered that the latter is merely a metaphor. There is as yet no international legislature proper in the international sphere. As to the role, and weaknesses, of treaties as a basis for a legal system and a mechanism for securing change, see Simma in The Structure and Process of International Law (eds MacDonald and Johnston, (1983), pp 485–512.

So-called law-making treaties have been concluded ever since international law came into existence. It was not until the nineteenth century, however, that they came to acquire world-wide importance, beginning with the Final Act of the Vienna Congress 1815. The following 19th century examples may also be mentioned: the Treaties of London of 1831 and 1839 providing for the neutralisation of Belgium (see § 96, n 2); the Declaration of Paris 1856 (see vol II of 7th ed of this work, § 177); the Geneva Convention of 1864 for the amelioration of the conditions of the wounded in armies in the field (see vol II of 7th ed of this work, § 118; and the Final Act of the Hague Peace Conference 1899 (see ibid, § 68 (4)). For a comprehensive list see Rühland, System der völkerrechtlichen Kollektivverträge (1929). See also Hudson’s International Legislation (1931–50), of which nine volumes have been published. The ILC considered dealing with this kind of treaty as subject to certain special considerations, and in its 1962 draft Articles on the Law of Treaties defined a ‘general multilateral treaty’ as ‘a multilateral treaty which concerns general norms of international law or deals with matters of general interest to States as a whole’. For various reasons it dropped this provision from its final draft Articles on the Law of Treaties, as explained in ILC Commentary (Treaties) Art 12: YBILC (1966), ii, pt 2, p 199.

Note also the emphasis sometimes placed on human rights treaties as not being ‘multilateral treaties of the traditional type concluded to accomplish the reciprocal exchange of rights for the mutual benefit of the contracting States’ but rather treaties whose object is the protection of individuals, even as against the state of their own nationality as well as all other contracting states: see, eg Effect of Reservations Opinion (1982), ILR, 67, pp 559, 568; Restrictions to the Death Penalty (Advisory Opinion OC-3/83) (1983), ILR, 70, pp 449, 466.

Nowadays it is unlikely that a small number of states would conclude a treaty possessing a general law-making character: this was not so formerly, eg the Final Act of the Vienna Congress 1815, was signed by only eight states. See also § 575, n 2. The practice of treaties being concluded under the auspices of the UN, after extensive preparation by the ILC, may come to be regarded as putting them in a special category as ‘law-making’ treaties: see Rosenne, Hag R, 86 (1954), pp 281–442, and above, § 574, at n 3; and Dehaussy, Recueil d’études de droit international en hommage à Paul Guggenheim (1968), pp 305–26.

Thus, the Hague Conventions regarding the rules of land warfare have been held to have become generally binding rules of international law: see vol II of 7th ed of this work, § 69a. The possibility of a rule set forth in a treaty becoming generally binding as a rule of customary international law is preserved by Art 38 of the Vienna Convention on the Law of Treaties. See generally, McNair, Treaties, pp 259–71; and see § 11, at n 12ff. As to ‘law-making’ treaties in relation to state succession, see Jenks, BY, 29 (1952), pp 105–44, and above, § 62, n 12; as to conflicts between law-making treaties, see Jenks, BY, 30 (1953), pp 401–53. In the North Sea Continental Shelf Cases the ICJ considered whether the 1959 Geneva Convention on the Continental Shelf had acquired the status of customary international law, and concluded that this had not by then happened: ICJ Rep (1969), p 43.

The question has been much discussed whether the UN Law of the Sea Convention 1982 is, at least in part, applicable as customary international law, or whether, because of the interrelationship between the various parts of the Convention and between its substantive and procedural provisions, it is exclusively a contractual treaty giving rise to rights and obligations only as between the parties. See Lee, AJ, 77 (1983), pp 541–68; and generally § 11, n 3, and § 283.

Thus, the effect of entering a reservation to such a provision, or denouncing a treaty containing such provisions, or becoming a party to such a treaty, is different from the effect in relation to a treaty merely constituting a consensual agreement inter partes. See Weil, AJ, 77 (1983), at pp 438–40.

ICJ Rep (1950), p 133. See also, in particular, the Separate Opinion of Judge McNair, pp 155–7. See also the Opinion of Judge Lauterpacht in the South West Africa (Petitioners) Case, ICJ Rep (1956), pp 48–9. See also §§ 88 and 626–7. In the case concerning Certain Expenses of the United Nations the ICJ regarded the Charter of the UN as ‘a multilateral treaty, albeit a treaty having certain special characteristics’, but even so applied to its interpretation the usual rules and principles applicable in general to the interpretation of treaties: ICJ Rep (1962), p 157. See also Ciobanu, Current Problems of International Law (ed Cassese, 1975), pp 3–79.

See generally on such a status or regime, McNair, Treaties, pp 255–71, 655–64; O’Connell, State Succession in International and Municipal Law (1967), 2, pp 12–22, 231ff; Jennings, Hag R, 121, (1967), ii, p 442; YBILC (1974), ii, pt 1, pp 204–6, paras (30)–(36); Klein, Statusverträge im Völkerrecht (1980); and § 1, n 6, and §§ 626–7.

Eg Belgium, established by treaty in 1831: see § 96, n 2, and McNair, Treaties, pp 268–9.

10  Thus in the Reparations for Injuries case the ICJ held that the provisions of the Charter of the UN invested the UN with an international status — an international personality — with an effect transcending the group of states comprising the membership of the UN. See §§ 7 and 627.

11  Eg the neutrality of Switzerland (see § 97; McNair, Treaties, pp 260–63) and the demilitarisation of the Aaland Islands. With regard to these Islands it should be noted that the Committee of Jurists appointed by the Council of the League took the view (Off J, Special Suppl, No 3, pp 17–19) that the convention, embodying ‘a settlement regulating European interests … constituted a special international status … for the Aaland Islands,’ and that ‘until these provisions are duly replaced by others, every State interested has the right to insist upon compliance with them.’ They were replaced by a Convention of 20 October 1921, between ten states, not including Russia; see § 237, n 2, and vol II of the 7th ed of this work, § 72 (8), and Strupp, Wört, i, p 22, for bibliography of Swedish, Finnish, and general literature upon the Aaland Islands question. See also Suontausta in ZöV, 13 (1951), pp 741–52; McNair, Treaties, pp 263–5; Hannum, Autonomy, Sovereignty, and Self-Determination (1990), pp 370–5. And see the Separate Opinion of Judge McNair in the Advisory Opinion on the Status of South West Africa for detailed reference to the report of the Commission of Jurists in the case of the Aaland Islands: ICJ Rep, 1950, pp 153–4. The ICJ construed Art 22 of the Covenant of the League of Nations as creating ‘an international status’ for the mandated territories: Status of South West Africa Case, ICJ Rep (1950), p 137. See also South West Africa Cases, ICJ Rep (1962), p 319, holding the mandate for South West Africa to have given rise to legal rights or interests on the part of all members of the League in the observance by the Mandatory of the terms of the mandate (at p 343). It is particularly in connection with those treaty restrictions upon the use of state territory which are often called ‘servitudes’ (see §§ 236–40) that parties other than the parties to the original treaty are likely to acquire an interest in their preservation.

For consideration of the Antarctic Treaty as establishing a regime with regulatory powers vested in certain states only (the Consultative Parties) but valid erga omnes, see Nussbaum, Rohstoffgewinnung in der Antarktis (1985); and see generally § 257.

12  Eg the Kiel Canal (see The Wimbledon, PCIJ (1923), Series A, No 1; § 185) and the Danube (see The European Commission of the Danube Case, PCIJ (1927), Series B, No 14; § 176). Similar suggestions have been made in respect of the Suez and Panama canals (§§ 184–6): see McNair, Treaties, pp 265–6.

13  See McNair, Treaties, ch 14; ILC Commentary (Treaties), Art 34, para (4) (YBILC (1966), ii, p 231). As to the acquisition of rights and obligations under a treaty by third states, see §§ 626–7.

This includes treaties provisionally in force under Art 25 of the Vienna Convention: see ILC Commentary (Treaties), Art 23, para (3); YBILC (1966), ii, p 211.

The obligation of good faith includes the obligation of a party to a treaty to abstain from acts calculated to frustrate the object and purpose of the treaty: see ILC Commentary (Treaties), Art 23, para (4); YBILC (1966), ii, p 211. See also § 620, n 2; and § 12, nn 6, 7, and § 105, as to the seventh ‘Principle of Friendly Relations’.

See vol I of 8th ed of this work, p 880, nn 4–8.

That assumption is frequently expressed in the form of the principle pacta sunt servanda, but it is not certain that this is the best formulation: see Anzilotti, pp 42–57; Verdross, pp 28–33; Kelsen, Das Problem der Souveränität und die Theorie des Völkerrechts (1920), and Allgemeine Staatslehre (1925), p 175. And see Harv Research (1935), pt III, pp 977–92; Chailley, La Nature juridique des traités internationaux (1932), pp 73–130; Scelle, ii, p 337; Strupp, Éléments, i, p 8; Whitton, RI (Paris), 18 (1936), pp 440–86, and, International Conciliation (Pamphlet No 313, October 1935); Kunz, AJ, 39 (1945), pp 180–97; Fitzmaurice, BY, 35 (1959), pp 194–6; Wehberg, AJ, 53 (1959), pp 775–86; McNair, Treaties, ch 30; YBILC (1966), ii, pp 210–11; Suganami, YB of World Affairs, 33 (1979), pp 243–56; Likashud, AJ, 83 (1989), pp 513–18. Cavaglier, Hag R (1929), ii, p 362, admits the fundamental nature of the rule pacta sunt servanda, but points out that the binding force of that rule has also been accepted by international custom. See also §§ 3–5, on the ‘initial hypothesis’.