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25. The question of Namibia was placed on the agenda of the Security Council as a ‘situation’ and not as a ‘dispute’. No member State made any suggestion or proposal that the matter should be examined as a dispute, although due notice was given of the placing of the question on the Security Council’s agenda under the title ‘Situation in Namibia’. Had the Government of South Africa considered that the question should have been treated in the Security Council as a dispute, it should have drawn the Council’s attention to that aspect of the matter. Having failed to raise the question at the appropriate time in the proper forum, it is not open to it to raise it before the Court at this stage.[…]
27. In the alternative the Government of South Africa has contended that even if the Court had competence to give the opinion requested, it should nevertheless, as a matter of judicial propriety, refuse to exercise its competence.[…]
29. It would not be proper for the Court to entertain these observations, bearing as they do on the very nature of the Court as the principal judicial organ of the United Nations, an organ which, in that capacity, acts only on the basis of the law, independently of all outside influence or interventions whatsoever, in the exercise of the judicial function entrusted to it alone by the Charter and its Statute. A court functioning as a court of law can act in no other way.[…]
32. Nor does the Court find that in this case the Security Council’s request relates to a legal dispute actually pending between two or more States. It is not the purpose of the request to obtain the assistance of the Court in the exercise of the Security Council’s functions relating to the pacific settlement of a dispute pending before it between two or more States. The request is put forward by a United Nations organ with reference to its own decisions and it seeks legal advice from the Court on the consequences and implications of these decisions.
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40. The Government of South Africa has also expressed doubts as to whether the Court is competent to, or should, give an opinion, if, in order to do so, it should have to make findings as to extensive factual issues. In the view of the Court, the contingency that there may be factual issues underlying the question posed does not alter its character as a ‘legal question’ as envisaged in Article 96 of the Charter. The reference in this provision to legal questions cannot be interpreted as opposing legal to factual issues. Normally, to enable a court to pronounce on legal questions, it must also be acquainted with, take into account and, if necessary, make findings as to the relevant factual issues.
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As to the position of the League, the Court found in its 1950 Advisory Opinion that: ‘The League was not, as alleged by [the South African] Government, a “mandatory” in the sense in which this term is used in the national law of certain States’. The Court pointed out that: ‘The Mandate was created, in the interest of the inhabitants of the territory, aid of humanity in general, as an international institution with an international object—a sacred trust of civilization’. Therefore, the Court found, (p. 162) the League ‘had only assumed an international function of supervision and control’ (I.C.J. Reports 1950, p. 132).
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52. Furthermore, the subsequent development of international law in regard to non-self-governing territories, as enshrined in the Charter of the United Nations, made the principle of self-determination applicable to al1 of them. The concept of the sacred trust was confirmed and expanded to all ‘territories whose peoples have not yet attained a full measure of self-government’ (Art. 73). Thus it clearly embraced territories under a colonial régime. Obviously the sacred trust continued to apply to League of Nations mandated territories on which an international status had been conferred earlier. A further important stage in this development was the Declaration on the Granting of Independence to Colonial Countries and Peoples (General Assembly resolution 1514 (XV) of 14 December 1960), which embraces all peoples and territories which ‘have not yet attained independence’.
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55. […] the League of Nations was the international organization entrusted with the exercise of the supervisory functions of the Mandate. Those functions were an indispensable element of the Mandate. But that does not mean that the mandates institution was to collapse with the disappearance of the original supervisory machinery. To the question whether the continuance of a mandate was inseparably linked with the existence of the League, the answer must be that an institution established for the fulfilment of a sacred trust cannot be presumed to lapse before the achievement of its purpose. The responsibilities of both mandatory and supervisor resulting from the mandates institution were complementary, and the disappearance of one or the other could not affect the survival of the institution.
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89. Undoubtedly, the Court does not possess powers of judicial review or appeal in respect of the decisions taken by the United Nations organs concerned. The question of the validity or conformity with the Charter of General Assembly resolution 2145 (XXI) or of related Security Council resolutions does not form the subject of the request for advisory opinion. However, in the exercise of its judicial function and since objections have been advanced the Court, in the course of its reasoning, will consider these objections before determining any legal consequences arising from those resolutions.
90. […] The mandatory Powers while retaining their mandates assumed, under Article 80 of the Charter, vis-à-vis all United Nations Members, the obligation to keep intact and preserve, until trusteeship agreements were executed, the rights of other States and of the peoples of mandated territories, which resulted from the existing mandate agreements and related instruments, such as Article 22 of the Covenant and the League Council’s resolution of 31 January 1923 concerning petitions. The mandatory Powers also bound themselves to exercise their functions of administration in conformity with the relevant obligations emanating from the United Nations Charter, which member States have undertaken to fulfil in good faith in all their international relations.
91. One of the fundamental principles governing the international relationship thus established is that a party which disowns or does not fulfil its own obligations cannot be recognized as retaining the rights which it claims to derive from the relationship.(p. 163)
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94. In examining this action of the General Assembly it is appropriate to have regard to the general principles of international law regulating termination of a treaty relationship on account of breach. For even if the mandate is viewed as having the character of an institution, as is maintained, it depends on those international agreements which created the system and regulated its application. […] The rules laid down by the Vienna Convention on the Law of Treaties concerning termination of a treaty relationship on account of breach [art. 60, para 3] (adopted without a dissenting vote) may in many respects be considered as a codification of existing customary law on the subject. […]
95. General Assembly resolution 2145 (XXI) determines that both forms of material breach had occurred in this case. […]
96. It has been contended that the Covenant of the League of Nations did not confer on the Council of the League power to terminate a mandate for misconduct of the mandatory and that no such power could therefore be exercised by the United Nations, since it could not derive from the League greater powers than the latter itself had. For this objection to prevail it would be necessary to show that the mandates system, as established under the League, excluded the application of the general principle of law that a right of termination on account of breach must be presumed to exist in respect of all treaties, except as regards provisions relating to the protection of the human person contained in treaties of a humanitarian character (as indicated in Art. 60, para. 5, of the Vienna Convention). The silence of a treaty as to the existence of such a right cannot be interpreted as implying the exclusion of a right which has its source outside of the treaty, in general international law, and is dependent on the occurrence of circumstances which are not normally envisaged when a treaty is concluded.
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122. For the reasons given above, and subject to the observations contained in paragraph 125 below, member States are under obligation to abstain from entering into treaty relations with South Africa in all cases in which the Government of South Africa purports to act on behalf of or concerning Namibia. With respect to existing bilateral treaties, member States must abstain from invoking or applying those treaties or provisions of treaties concluded by South Africa on behalf of or concerning Namibia which involve active intergovernmental co-operation. With respect to multilateral treaties, however, the same rule cannot be applied to certain general conventions such as those of a humanitarian character, the non-performance of which may adversely affect the people of Namibia. It will be for the competent international organs to take specific measures in this respect.
123. Member States, in compliance with the duty of non-recognition imposed by paragraphs 2 and 5 of resolution 276 (1970), are under obligation to abstain from sending diplomatic or special missions to South Africa including in their jurisdiction the Territory of Namibia, to abstain from sending consular agents to Namibia, and to withdraw any such agents already there. They should also make it clear to the South African authorities that the maintenance of diplomatic or consular relations with South Africa does not imply any recognition of its authority with regard to Namibia.
124. The restraints which are implicit in the non-recognition of South Africa’s presence in Namibia […] impose upon member States the obligation to abstain from (p. 164) entering into economic and other forms of relationship or dealings with South Africa on behalf of or concerning Namibia which may entrench its authority over the Territory.
125. In general, the non-recognition of South Africa’s administration of the Territory should not result in depriving the people of Namibia of any advantages derived from international co-operation. In particular, while official acts performed by the Government of South Africa on behalf of or concerning Namibia after the termination of the Mandate are illegal and invalid, this invalidity cannot be extended to those acts, such as, for instance, the registration of births, deaths and marriages, the effects of which can be ignored only to the detriment of the inhabitants of the Territory.
126. As to non-member States, although not bound by Articles 24 and 25 of the Charter, they have been called upon […] to give assistance in the action which has been taken by the United Nations with regard to Namibia. In the view of the Court, the termination of the Mandate and the declaration of the illegality of South Africa’s presence in Namibia are opposable to all States in the sense of barring erga omnes the legality of a situation which is maintained in violation of international law: in particular, no State which enters into relations with South Africa concerning Namibia may expect the United Nations or its Members to recognize the validity or effects of such relationship, or of the consequences thereof.