WARSAW, Poland — President Barack Obama says the U.S. is sending an additional 1,000 U.S. troops to Poland as part of a NATO effort to reinforce its presence on the alliance’s eastern flank.

The U.S.-led battalion is one of four that NATO will begin rotating through the region. The move is meant to act as a deterrent to Russia.

Obama is touting the decision in remarks to reporters after a meeting with Poland’s President Andrzej Duda. The U.S. president thanked Poland for its contributions to the campaign against the Islamic State, including its F-16 aircraft and special forces trainers.

He called Poland “a lynchpin in the defense of NATO’s eastern flank.”