Russia threatened to aim nuclear missiles at Danish warships if Denmark joins NATO's missile defense system, in comments Copenhagen called unacceptable and NATO said would not contribute to peace.
Denmark said in August it would contribute radar capacity on some of its warships to the missile shield, which the Western alliance says is designed to protect members from missile launches from countries such as Iran.
Moscow opposes the system, arguing that it could reduce the effectiveness of its own nuclear arsenal, leading to a new Cold War-style arms race.