The US and Russian militaries have accused each other of unsafe actions after an American guided-missile cruiser and a Russian destroyer came within 50 metres of each other in the East China Sea.
The US 7th Fleet said the Russian destroyer put the safety of the USS Chancellorsville and its crew at risk on Friday, forcing it to reverse all engines at full throttle to avoid a collision.
It said a helicopter that was operating at sea was preparing to land on the Chancellorsville, which was travelling on a steady course, when the Russian destroyer, travelling behind the US ship, sped up and got as close as 15 to 30m.
Clay Doss, spokesman for the Japan-based 7th Fleet, says no one was injured and he wasn't aware of any damage to the ship.
"We consider Russia's actions during this interaction as unsafe and unprofessional and not in accordance with the International Regulations for Preventing Collisions at Sea (COLREGS), 'Rules of the Road,' and internationally recognized maritime customs," the 7th Fleet said in a statement.
The Russian military accused the Chancellorsville of making a dangerous manoeuvre by crossing the path of the Russian destroyer Admiral Vinogradov.
It said in a statement that the US cruiser "suddenly changed direction and crossed the path of Admiral Vinogradov just 50 metres away," forcing the crew of the Russian ship to make a quick manoeuvre to avoid collision.
The Russian military said its navy sent a radio message in protest.
With US-Russian relations at post-Cold War lows over the Ukrainian crisis, the war in Syria and Moscow's meddling in the 2016 US presidential election, the Russian and US militaries have frequently exchanged accusations of what they describe as unsafe manoeuvre by the other side's warplanes and navy ships.
