Veteran U.S. Senator Lindsey Graham urged on Tuesday a no-fly zone in Syria’s war-ravaged Idlib town and said that he appreciates Turkey’s moves in the face of heavy Assad regime and Russian aggression in the area.

"Very much appreciate what Turkey is doing to stand with the people of Idlib, Syria. It is time for the world, including the United States, to declare a no-fly zone over Idlib before the humanitarian crisis escalates," he said.

"Russia’s Putin and Syria’s Assad are behaving like war criminals. There is one thing I have learned from Syria: ignoring a problem always makes it worse," he added.

Attacks by the forces of the Bashar Assad regime have killed 55 Turkish soldiers in the past month in Idlib. President Recep Tayyip Erdoğan has threatened to push back Assad forces if they do not pull back to predetermined lines.

Regime airstrikes targeting Turkish troops heightened tensions between pro-opposition Turkey, Assad and its ally, Russia. The latest crisis stems from a Russian-backed Assad regime military campaign to retake Idlib province, which is the last opposition-held stronghold in Syria.

The offensive, which began Dec. 1, has triggered the largest single wave of displacement in Syria's nine-year war, sending nearly 950,000 people fleeing to areas near the Turkish border for safety.