NATO and U.S. authorities are in close contact about force posture, a NATO official said on Wednesday after Romania's defense ministry said allies were notified of U.S. plans to cut the number of troops stationed on Europe's eastern flank.

"Adjustments to U.S. force posture are not unusual," the NATO official said, adding that "even with this adjustment, the U.S. force posture in Europe remains larger than it has been for many years."

"NATO and U.S. authorities are in close contact about our overall posture – to ensure NATO retains our robust capacity to deter and defend, and the U.S. authorities informed NATO of this adjustment in advance," the official said.