USS Carter Hall, a dock landing ship of the United States Navy, sets sail in the Bosphorus, on its way to the Black Sea, in Istanbul, Turkey, March 17, 2017. REUTERS/Murad Sezer

(Reuters) - Russia’s defense ministry said on Tuesday it regarded U.S. naval patrols in the Black Sea as a potential threat to its safety because it was unclear what kind of missiles the ships were carrying, the RIA news agency reported.

Russia, which annexed Ukraine’s Crimea in 2014, has its own Black Sea Fleet based at Sevastopol.