The US Embassy in Ukraine has published a respective statement on its Twitter account.
"The Russian court's decision to unjustly extend the detention of the Ukrainian sailors is appalling. Russia must immediately return to Ukraine its detained personnel and vessels and respect Ukraine's sovereignty and territorial integrity," the embassy said.
As reported, on April 17, Moscow's Lefortovo District Court extended the detention of Ukrainian sailors captured during an attack on Ukrainian vessels in the Kerch Strait last November.
On April 16, Ukraine submitted a request to the International Tribunal for the Law of the Sea for the prescription of interim measures under article 290, paragraph 5, of the United Nations Convention on the Law of the Sea in a dispute between Ukraine and the Russian Federation concerning "the immunity of three Ukrainian naval vessels and the twenty-four servicemen on board."
On November 25, 2018, Russian border guards fired on and seized three Ukrainian naval vessels that were on a voyage from Odesa to Mariupol, as well as their crews. Twenty-four Ukrainians were captured, and three of them were injured.
A Russian-controlled "court" in the occupied Crimea arrested all detained Ukrainian soldiers for allegedly illegally crossing the Russian border. They are now being held in a pre-trial detention center in Moscow.
On January 24, 2019, the Parliamentary Assembly of the Council of Europe adopted a resolution officially demanding that Russia treat Ukrainian seamen captured in the Kerch Strait in accordance with the Geneva Convention relative to the Treatment of Prisoners of War.