The U.S. expressed concern over Russian military aircraft flying apparent simulated attack passes near a U.S. destroyer in the Baltic Sea over the course of two days this week.
The U.S. says two Russian attack aircraft flew around 20 passes near the USS Donald Cook while the ship was in international waters.
"There have been repeated incidents over the last year where the Russian military, including Russian military aircraft, have come close enough to each other - or have come close enough to other air and sea traffic - to raise serious safety concerns. And we continue to be concerned about this behavior," White House spokesman Josh Earnest said.
The Donald Cook had just come from a port visit in Gdynia, Poland, when the flyovers occurred. It was headed out to sea with a Polish helicopter on board.
NATO has been asked to provide a permanent presence of battalion-sized deployments of allied troops in the Baltic States. Moscow denies any intention to attack the Baltic states.