NATO chief Jens Stoltenberg on Friday urged the United States and Turkey to "sit down and find solutions" to a crisis in relations between the two key members of the military alliance.

"I only urge the United States and Turkey to sit down and find solutions because it is important for the alliance that we are able to work closely together, especially in that region, because Turkey is a key for our fight against terrorism," Stoltenberg told AFP in an interview.