The NATO buildup in the Black Sea is part of the alliance's strategy to expand its military presence along Russia's borders. The move would destabilize the situation in the region, says a report in Sputnik.
Russian state media reported earlier this month that the USS Porter, a U.S. naval destroyer, had entered the Black Sea on a routine deployment, a move it said raised hackles in Moscow because it had recently been fitted with a new missile system.
Under the Montreux Convention, countries which don't have a Black Sea coastline cannot keep their warships there for more than 21 days. NATO members Turkey, Romania and Bulgaria are all Black Sea Basin countries, says Reuters.
Russia is closely watching the US and NATO military activities in the Black Sea which may also involve Ukraine and other countries, Russia’s Permanent Representative to NATO Alexander Grushko said.
"It is clear that we are going to react to such things with an aim to ensure reliable security on Russia’s southern borders," he added.
NATO is considering what more it can do to deter what it sees as growing Russian aggression. Moscow says it poses no threat to the alliance.