27 November 2018 Ukraine today took steps to alert the international tribunal that is considering Russia’s violations of the 1982 U.N. Convention on the Law of the Sea in the Black Sea, Sea of Azov, and Kerch Strait, of recent actions by Russia that have significantly aggravated the parties’ dispute.

In a letter submitted to the tribunal, Ukraine described Russia’s ongoing pattern of harassment against Ukrainian and international vessels seeking to transit the Kerch Strait and navigate to Mariupol, Berdyansk, and other Ukrainian ports.

Russia’s actions effectively closed the Kerch Strait to all vessels, resulting in protests not only by Ukraine, but also by authorities representing other Black Sea littoral States, including the European Union and Turkey, which both insisted on freedom of passage through the Strait.

Russia’s latest actions, including firing and seizure of Ukrainian naval vessels, mark a serious escalation of a months’-long pattern, in which vessels flagged both to Ukraine and to third states have repeatedly faced obstacles to navigation, including extended stops that have caused significant economic losses. Only vessels heading to Ukrainian ports have been affected by such stops; vessels bound for Russian ports in the Sea of Azov have not reported similar interference.

Ukraine has protested Russia’s actions, has raised them with its allies and, through this latest action, has demonstrated its intent to challenge Russia’s conduct through appropriate legal means