On 24 December 2003, at Kerch, the Treaty between the Russian Federation and Ukraine on Cooperation in the Use of the Sea of Azov and the Kerch Strait was concluded. Two originals, equally authentic Russian and Ukrainian texts. Signed by Presidents Vladimir Putin and Leonid Kuchma. Article 5: ratification; it enters into force on the date of exchange of instruments of ratification. Ukraine ratified it by Law 1682-IV of 20 April 2004; Russia by Federal Law 23-FZ of 22 April 2004. Ukrainian text: document 643_205.

The preamble invokes the Treaty on Friendship, Cooperation and Partnership of 31 May 1997 and the Treaty on the State Border of 28 January 2003, notes the economic importance of the Sea of Azov and the Kerch Strait, and provides that all issues pertaining to those waters must be resolved only by peaceful means, jointly or by agreement of the two States, preserving the Azov–Kerch water area as an integral economic and natural complex.

Article 1: the Sea of Azov and the Kerch Strait historically constitute internal waters of the Russian Federation and Ukraine. The Sea of Azov shall be delimited by the state border line in accordance with an agreement between the Parties. Issues concerning the water area of the Kerch Strait shall be resolved by agreement between the Parties. The Treaty itself does not draw the line.

Article 2(1): merchant vessels and warships, as well as other State vessels used for non-commercial purposes, flying the flag of the Russian Federation or Ukraine, enjoy freedom of navigation in the Sea of Azov and the Kerch Strait. Article 2(2): merchant vessels flying the flags of third States may enter the Sea of Azov and pass through the Strait if bound for or returning from a Russian or Ukrainian port. Article 2(3): warships and other non-commercial State vessels of third States may enter and pass if making a visit or business call to a port of one of the Parties at its invitation or with its permission, agreed with the other Party. This is not a handbook of vessel inspection.

Article 3: Russian–Ukrainian cooperation — navigation, including its regulation and navigational-hydrographic support, fisheries, protection of the marine environment, environmental safety, and search and rescue — shall be ensured by existing agreements and, where appropriate, by new ones. Article 4: disputes on interpretation and application shall be settled by consultations and negotiations, and by other peaceful means chosen by the Parties. Article 5(2): amendments shall be drawn up as separate protocols, entering into force by the same ratification procedure.

The Verkhovna Rada recorded termination of document 643_205 on 25 March 2023, on the basis of Law 2948-IX. Russia’s Federation Council approved a denunciation bill in June 2023. Those later acts do not alter the 2003 text set out here.

The port of Kerch, the place of signature, not the signing room. Wikimedia Commons, free licence.

For context: Treaty Between the Russian Federation and Ukraine on Cooperation in the Use of the Sea of Azov and the Kerch Strait. The text: Договір між Україною та Російською Федерацією про співробітництво у використанні Азовського моря і Керченської протоки.