EU leaders of all 28 member states declare their readiness to strengthen support for the affected regions of Ukraine after Russia blocked shipping in the Sea of Azov.

"The European Council expresses its utmost concern regarding the escalation at the Kerch Straits and the Azov Sea and Russia's violations of international law," the Council said in its conclusions after a summit in Brussels on December 13.

"The European Council requests the immediate release of all detained Ukrainian seamen as well as the return of the seized vessels and free passage of all ships through the Kerch Straits. The EU stands ready to adopt measures to strengthen further its support, in particular in favour of the affected areas of Ukraine," it said.

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The European Council reconfirmed its commitment to international law, the sovereignty, territorial integrity and independence of Ukraine and the EU's policy of non-recognition of the illegal annexation of Crimea. "There is no justification for the use of military force by Russia," it said.

As UNIAN reported earlier, High Representative of the European Union for Foreign Affairs and Security Policy / Vice-President of the European Commission Federica Mogherini said on December 10 that practical support for the affected regions of Ukraine after the blockade by Russia of shipping in the Sea of Azov and the Kerch Strait is more important than new sanctions over that blockade. Speaking before the EU summit, she said that the EU was ready to expand substantial assistance to Ukraine.

On November 25, Russia seized three Ukrainian navy vessels and their combined crew of 24 off the coast of Russian-occupied Crimea and accused them of illegally entering Russian waters. Ukraine has said Russia captured the two small gunboats and one tugboat illegally and accused Moscow of military aggression.