No justification for use of military force against Ukrainian ships and naval personnel, says NATO chief Stoltenberg.

NATO’s chief on Monday has called on Russia to immediately free Ukrainian ships and soldiers seized in a naval confrontation on Sunday.

“NATO allies support Ukraine’s territorial integrity and sovereignty. There is no justification for the use of military force against Ukrainian ships and naval personnel. We urge Russia to free Ukrainian ships and soldiers at once,” Secretary-General Jens Stoltenberg told a news conference after a NATO-Ukraine emergency meeting in Brussels on Monday.

Russia seized three Ukrainian navy ships off Crimea in the Sea of Azov on Sunday.

Russia said the vessels had ignored calls to stop, sparking military action.

Russia intervened as the Ukrainian warships were relocating from Odessa to the Port of Mariupol in the Sea of Azov.

The Ukrainian Navy accused Russia of opening fire on its warships off Crimea, asserting that crew members were wounded and its vessels were seized by Russia.

Russia and Ukraine have been at loggerheads since 2014, when Russia annexed Crimea after a controversial referendum.

Turkey, as well as the UN General Assembly, viewed the annexation as illegal.

Ukraine has also blamed Russia for separatist violence in eastern Ukraine, near the border with Russia.