The ministry says Ukraine remains the coastal state with regard to the waters around Crimea / Photo from UNIAN

Ukraine's Ministry of Foreign Affairs demands the immediate release of a Ukrainian fishing vessel and its crew detained by Russia in the Black Sea near the Russian-occupied Crimea.

"Ukraine protests in the strongest terms the unlawful detention this morning by the Russian Federation of a Ukrainian fishing vessel and its crew in the vicinity of the Crimean coast. Ukraine demands the immediate release of the fishing vessel and its crew," the ministry said in a statement on May 4.

Read alsoRussian coastguards detain Ukrainian fishing vessel off Crimea coast

As the UN General Assembly has made clear, Russia's unlawful aggression does not alter the status of Crimea as Ukraine's sovereign territory, the ministry recalled.

Ukraine remains the coastal state with regard to the waters around Crimea, including the territorial sea extending 12 nautical miles from its coast.

"Russia's detention of this fishing vessel usurps Ukraine's sovereign rights in those waters and as such is a manifest violation of the UN Convention on the Law of the Sea, as well as of customary international law," the ministry said.

The vessel was detained by Russian border guards near the Crimean coast on the morning of May 4. There were five crewmembers on board the ship.

Some media reported that the Russian border guards had detained the small-sized YaMK-0041 fishing vessel to the west of Cape Tarkhankut.

Spokesman for Ukraine's State Border Guard Service Oleh Slobodyan said there was no contact with the crew and the Ukrainian authorities were examining the circumstances of the incident.

"It's hard to say how and why the ship violated the state border of Ukraine and turned to be in the zone that is considered to be temporarily occupied by Russia," he said. In his opinion, most likely, the captain of the ship decided to go where, in his opinion, the catch would be better, having thus neglected the risk of detention by the border guards of the occupation forces.