The US Navy routinely operates in the Black Sea, but a warship placement would now send a specific message to Moscow that the United States is watching closely, the official said.
The United States is obliged to notify its intention to enter the Black Sea 14 days in advance, according to a 1936 treaty that gives Turkey control of the straits to enter the sea. It is not clear whether a warning has already been sent.
The defense official also said that the Navy continues to fly reconnaissance aircraft in international airspace over the Black Sea to monitor Russian naval activity and any troop movements in Crimea.
On Wednesday, two American B-1 bombers conducted missions over the Aegean Sea.
Although the United States does not see the buildup of Russian forces as a stance for offensive action, the official told CNN that “if something changes, we will be ready to respond”. The current assessment is that the Russians are conducting training and exercises and intelligence has not indicated military orders for further action, the official said, but noted that they are well aware that this could change at any time.
The Biden government and the international community have expressed concern about increased tensions between Ukraine and Russia. In recent weeks, President Joe Biden, Secretary of State Tony Blinken, Defense Secretary Lloyd Austin, Joint Chiefs President Mark Milley and national security adviser Jake Sullivan have spoken to their Ukrainian colleagues.
“We are concerned about the recent escalation of Russian aggressions in eastern Ukraine, including the reliable reports emanating about Russian troop movements on the borders of Ukraine and in occupied Crimea,” said State Department spokesman Ned Price , this week.
“We asked Russia for an explanation for these provocations, but most importantly, what we signaled directly to our Ukrainian partners is a message of tranquility,” he said.
Pentagon spokesman John Kirby said this week that it is important “that all sides comply with the Minsk Agreement” and “that Ukraine’s territorial integrity and sovereignty are respected by Russia”.
On Thursday, German Chancellor Angela Merkel asked Russian President Vladimir Putin to withdraw troops to lessen the situation, according to a German government spokesman.
According to a Kremlin reading on the summons, Putin accused Kiev of “provocative actions”.