A U.S. Navy warship is on its way to the Black Sea as part of the ongoing response to Russia's actions in Ukraine, State Department officials said.
In the immediate aftermath of Russia's takeover of Crimea, the guided-missile destroyer USS Truxtun sailed into the Black Sea, where it conducted exercises with the Bulgarian and Romanian navies, practicing basic maneuvers and drills.
However, the Truxtun left the Black Sea March 21 to continue its scheduled deployment as part of the George H.W. Bush Carrier Strike Group, currently in the Middle East. A new Navy warship in the Black Sea would be a replacement for the Truxtun, said officials.
The U.S. Navy would not confirm which ship it would be sending into the area. But two destroyers -- the USS Donald Cook and the USS Ramage -- are currently in the vicinity, taking part in an exercise in the eastern Mediterranean with the Greek and Israeli navies.
"We are making plans to meet the intent vocalized by (U.S. and NATO officials) to lay out a sustainable maritime presence in the eastern Mediterranean and the Black Sea, but we do not have anything to announce at this time," said Capt. Gregory Hicks of the U.S. European Command. He said the Navy routinely operates ships in the Black Sea to demonstrate U.S. commitment to working closely with allies in the region.
On Thursday, Russian Foreign Minister Sergei Lavrov criticized the deployment of U.S. warships in the Black Sea during a joint press conference with Kazakhstan's foreign minister.
According to Russian media reports, Lavrov accused the U.S. of violating the Montreux Convention -- a 1936 international agreement that restricts the passage through the Bosporus Straits and the Dardanelles of naval ships not belonging to Black Sea states.
Meawnhile, U.S. and NATO leaders have expressed concern over Russia amassing tens of thousands of troops on its border with Ukraine.
Along with a set of sanctions against Russia, the U.S. has been bolstering its military presence throughout the region in a show of force to reassure allies and improve the military's ability to respond to a crisis.
"Obviously, we're working a diplomatic track, but we need to have things in place that do reassure our allies in case the diplomatic track takes longer than we want or while we try to make progress on it," State Department deputy spokeswoman Marie Harf said during a press briefing on Wednesday.
In recent weeks the U.S. has sent six additional F-15s to augment NATO's Baltic air policing mission, and a dozen F-16s to Poland to train with the Polish air force. Additionally, in the midst of increasing tensions, the Pentagon announced Wednesday that it was sending 175 more Marines to Romania, where 300 are already present. But officials said the move was unrelated to the current crisis between Ukraine and Russia.
In a sign that the crisis is deepening, NATO officials suspended all "practical civilian and military cooperation" with Russia Wednesday and announced that NATO would intensify its cooperation with Ukraine.