CYIL vol. 14 (2023)

ERNEST PETRIČ CYIL 14 (2023) and did not become part of international treaty law does not mean that the work of the Commission remained without any impact on the international legal assessment of those legal issues to which these drafts referred. In any case, these drafts indicate that their content is considered by the Commission, i.e., by the UN organ authorized for the progressive development of international law and its codification, to be an expression of existing state practice, even if the practice is not yet sufficient, uniform, and prevailing so that it would lead States to complete the codification by ratifying them. 3. The new challenges and methods of work of the Commission The new era, after the end of the bloc division of the world, after the end of the Cold War, opened up more opportunities for States to agree on the codification of international law in certain areas more directly, within the framework of the GA of the UN or at specially convened international conferences without direct involvement of the Commission. This new cooperative spirit was also relevant from the point of view of the development of international law. This was true for regulation by international law of important environmental issues, especially the issues of climate change and protection of environment, but also the issues of human rights. In the absence of its major codification topics, the Commission started to focus more on the consideration, preparation, and adoption of “principles”, “conclusions”, or “guidelines” regarding interpretation of norms of international law present in already binding international conventions. The Commission’s efforts to help better understand the concepts and institutes of international law, which was and still is experiencing an extraordinary development and expansion especially after the turn of the millennium and is the result of internationalization and globalization of virtually all areas of human life and work, also belongs to this new period. The characteristics of this time, after the end of the Cold War until today is on the one hand, the extraordinary development and proliferation of international law, but at the same time, the Commission had a less exposed role in this. This does not mean that the Commission did not perform important work by explaining and defining important institutes and concepts of international law, among others, those related to international treaty law. Specifically, regarding issues that were not elaborated sufficiently by the Vienna Convention on the Law of Treaties (1969). 17 Inter alia , we have in mind the Commission’s “conclusions” on the impact of a later agreement or consensual practice on interpretation of a valid international treaty, 18 the “guiding rules” on problems and the impact of reservations to the provisions of multilateral international treaties, 19 the “guide” on the problem of the provisional application of international treaties not yet ratified. 20 This also includes the draft articles on the impact of armed conflicts on international treaties. 21 Or projects of the 17 These are some of the issues that were left undefined in the Vienna convention, mainly due to the modest scope or the large contradictions within relevant States’ practice. 18 Conclusions on Subsequent Agreements and Subsequent Practice in Relation to Interpretation of Treaties, see ILC Report, A/73/10, paras 39–52. 19 The Commission in 2011 adopted and submitted the »Guide to Practice on Reservations to Treaties« to the General Assembly for further processing and to States for use (text see Official Records of the GA, 66 th session, Supplement No. 10 (A/66/10 and Add. 1). 20 The Commission adopted a Guide to Provisional Application of Treaties, see ILC Report, A/76/10, 2021, paras. 41–52. 21 Articles on the Effect of Armed Conflict on Treaties; the Commission adopted the draft articles in 2011 and forwarded them to the General Assembly for further processing; (Text see Annex to GA res. 66/99, 9. 12. 2011).

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