The European Union expects that the Russian Federation will restore freedom of passage via the Kerch Strait.

"We expect Russia to restore freedom of passage at the Kerch strait and urge all to act with utmost restraint to de-escalate the situation immediately," EU Spokesperson for Foreign Affairs and Security Policy/European Neighbourhood Policy and Enlargement Negotiations Maja Kocijancic said in a statement on the escalating tensions in the Sea of Azov on November 25.

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"The tensions in the Azov Sea and Kerch Strait have increased dangerously today [November 25], after an incident this morning between Russian and Ukrainian naval vessels as the latter were attempting to pass through the Kerch strait as well as subsequent developments, including the closure of the strait for traffic by Russian authorities and reported seizures of Ukrainian vessels and shots being fired at them," the statement said.

On Sunday morning, Russia blocked the Kerch Strait passage between the Black Sea and the Sea of Azov. Two small-sized armored artillery boats, the 'Berdiansk' and the 'Nikopol,' together with the 'Yany Kapu' tugboat – all belonging to Ukraine's Navy – were unable to cross the Kerch Strait. They were moving from the port of Odesa in the Black Sea to the port of Mariupol in the Sea of Azov. Later all the three boats with 23 people on board were captured by Russia's special forces on Sunday evening. Six Ukrainian navy men were reportedly wounded; two of them were in serious condition.