Despite the incident, the Ukrainian Navy's ships continue performing their tasks in keeping with international law.

Russia's 'Don' coast guard ship has rammed a Ukrainian tugboat amid the transfer of Ukrainian ships from the port of Odesa to the port of Mariupol in the Sea of Azov.

"The 'Don' coast guard ship rammed our tugboat, as a result of which the main engine of the ship was damaged," the Ukrainian Navy said on Facebook on Sunday morning.

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It also damaged the shell plating and guard railing of the Ukrainian tugboat, and its life raft was lost, it said.

The incident happened on Sunday, November 25.

In the video shot from the Russian attacker ship's cockpit, the captain is heard yelling out commands, heavily swearing.

Faster, come on! Good job! Crush it from the starboard side! F***ing crush it from the right! Crush it! I'll f***ing get it here. Press it. Midships! Come on, come on! F***ing press it! F***ing port 5. Port 10! Stop engine! Stop engine! Take hold on board! Reverse! Reverse! F***ing reverse! Come on! F***ing come on! Hold on everyone! F***ing b***h! Hold on board!

After the ship rammed the tug, one of the crewmen is heard saying "That was great!"

"A group of vessels, namely two small-sized 'Berdiansk' and 'Nikopol' armored artillery boats and the 'Yany Kapu' (Yanı Qapı) tugboat of Ukraine's Navy were carrying out a planned transfer from the port of Odesa to the port of Mariupol of the Sea of Azov today, November 25. Notification about the transfer plans was done in advance in accordance with international rules to ensure safe navigation. Yet, contrary to the UN Convention on the Law of the Sea and the Treaty between Ukraine and the Russian Federation on Cooperation in the Use of the Sea of Azov and the Kerch Strait, Russian ships – Sobol-class patrol boats, the 'Don' coast guard ship, Mangust-class patrol boats, and the 'Suzdalets' corvette – carried out openly aggressive acts against the ships of the Ukrainian Navy," the Navy said.

The Russian dispatcher service refuses to ensure the right to freedom of navigation, guaranteed by international agreements, it said.

Despite the incident, the Ukrainian Navy's ships continue performing their tasks in keeping with international law.

The Ukrainian side says that all illegal actions have been recorded by the crews of the ships and the command of Ukraine's Navy and reports will be handed over to the respective international agencies.