This article analyzes the political and legal features of concluding and implementing international treaties by Ukraine under martial law caused by the full-scale armed aggression of the Russian Federation. It substantiates that international treaties during wartime have transformed from traditional diplomatic instruments into key mechanisms for ensuring national security, state functioning, humanitarian protection, economic stability, and international accountability of the aggressor. The research examines changes in Ukraine’s treaty-making practice under extraordinary conditions, focusing on procedural adaptations, accelerated negotiations, temporary application of treaties, and the increased use of intergovernmental agreements, memoranda, and political declarations. Particular attention is paid to the compliance of such practices with international law, especially the Vienna Convention on the Law of Treaties of 1969, and Ukrainian national legislation, which allows treaty-making even under martial law. This article highlights priority areas of treaty activity, including security and defense cooperation, humanitarian assistance, economic and financial support, post-war recovery, and mechanisms for compensation and prosecution of international crimes. It is emphasized that Ukraine has managed to preserve legal legitimacy, maintain international legal personality, and simultaneously lay the foundations for post-war reconstruction and European integration. The study concludes that Ukraine’s experience under martial law demonstrates the formation of a new, adaptive, and strategically oriented treaty policy that strengthens both national resilience and the international legal order.

Key words: international treaties, martial law, foreign policy, legal regime, contractual activity, security, humanitarian law, international responsibility, Ukraine, aggression.

References

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