Article 51 of unclos at 40: Military Training as Other Legitimate Activities?

Article 51 of the United Nations Convention on the Law of the Sea (unclos) governs the legitimate activities of an immediately adjacent neighbouring state within certain areas of an archipelagic state’s archipelagic waters, utilising open-textured terms and subsequent bilateral agreements to balance states’ interests. In the context of both the signing of the 2022 Expanded Framework Agreements between Indonesia and Singapore and the 40-year anniversary of the adoption of unclos, this article examines the interpretation and application of Article 51 in respect of military training activities. This analysis demonstrates that the purposively ambiguous wording of the exceptional ‘Singapore Clause’ is best understood in the light of Singaporean and Indonesian negotiation crafting, as well as their subsequent implementation efforts (1995–2022). On military training activities, the states have consistently sought to conclude bilateral arrangements which align with the object and purposes of an Article 51 bilateral agreement in all but name.