“Our trust with the U.S. has been damaged. It’s not like we can say ‘a proposal has been made so we will accept it.’ These are serious issues. Trust should be re-built before we can talk about these details,” he said.

Çavuşoğlu’s remarks came two days after U.S. Secretary of State Rex Tillerson suggested building a 30-kilometer deep “security zone” along the Syrian border with Turkey at a meeting with Çavuşoğlu in Paris.