Russian ships last month opened fire on three Ukrainian navy vessels as they tried to pass through the Kerch Strait from the Black Sea to the Sea of Azov, and detained the 24 Ukrainian crew members.

Pentagon spokesman Eric Pahon said Ukraine's Admiral Ihor Voronchenko is meeting Thursday and Friday with US Chief of Naval Operations Admiral John Nicholson.

Nicholson and other Pentagon officials "will reiterate the US support for Ukraine's sovereignty and territorial integrity within its internationally recognized borders, extending to its territorial waters, as well as the right of its vessels to traverse international waters," Pahon told AFP.

Defense Secretary Jim Mattis earlier this month blasted the Russian navy's "brazen" violation of a treaty that allows both Russian and Ukrainian ships free passage in the Kerch Strait.

Pahon said the US government supports "Ukraine in its pursuit of a diplomatic and peaceful solution to the ongoing Russian aggression, including Russia's recent unprovoked attack on Ukrainian naval vessels in the Black Sea."

Ukraine's foreign minister on Thursday called for a speedy international response to Russia's "aggression" after it seized the three Ukrainian navy ships and 24 sailors.

The confrontation at sea on November 25 was the first open military incident between Kiev and Moscow since 2014 when Russia annexed the Crimean peninsula and a conflict erupted in eastern Ukraine between pro-Russia separatists and government forces, which has claimed more than 10,000 lives.