Supplying Ukraine With Weapons Due to the Russian Aggression: Legal Justification

Abstract

International law prohibiting the use of force in international relations provides for the support of Ukraine as a victim of the Russian aggression. The possibilities of Ukraine’s resistance to the Russian aggression, which began in 2014 and took a full-scale form after 24. February 2022, depend on the required amount of weapons provided to Ukraine.

This paper discusses several provisions justifying the legality of providing Ukraine with weapons in the aftermath of the Russian aggression, namely (1) Article 51 of the UN Charter that guarantees the inherent right of individual and collective self-defence; (2) the Briand- Kellogg Pact 1928 establishing the obligations erga omnes partes; and (3) the Articles on the Responsibility of States for Internationally Wrongful Acts of 2001 that deal with the legal consequences arising from serious breaches of obligations arising from peremptory norms of general international law and enshrining positive duty for states to cooperate in order to bring an end to serious breaches of jus cogens norms, as well as obligations erga omnes.

Keywords: Russian aggression, supplying weapons, individual self-defence, collective self- defence, Article 51 of the UN Charter, the Briand-Kellogg Pact, Articles 40-41 of the ARSIWA