FILE PHOTO: U.S. Senator Lindsey Graham (R-SC) attends an event celebrating the anniversary of the White House's Women’s Global Development and Prosperity (W-GDP) initiative at the State Department in Washington, U.S., February 12, 2020. REUTERS/Leah Millis

WASHINGTON (Reuters) - U.S. Senator Lindsey Graham on Thursday called for the establishment of a no-fly zone over Syria’s Idlib and called on President Donald Trump to help stop the killing of civilians there by Syrian government forces backed by Russia and Iran.

“The world is sitting on its hands and watching the destruction of Idlib by Assad, Iran, and the Russians,” Graham, a Republican and an ally of Trump, said in a statement. “I am confident if the world, led by the United States, pushed back against Iran, Russia, and Assad that they would stand down, paving the way for political negotiations to end this war in Syria.”

Syrian President Bashar al-Assad’s forces have pushed hard in recent months to retake the last large rebel-held region in northwestern Syria after nine years of war that has displaced millions and killed hundreds of thousands.

Turkey has sent thousands of troops and heavy military hardware into Idlib province in an incursion to back the rebels against the offensive and have come under multiple attacks by Syrian government forces backed by Moscow.

Late on Thursday, Governor of Turkish southern province of Hatay bordering Syria, said 22 soldiers were killed in an air strike by Syrian government forces in Idlib. But war monitor Syrian Observatory said at least 34 Turkish soldiers were killed.

Kay Bailey Hutchison, U.S. Ambassador to NATO, responding to the latest incident in a briefing, said she hoped that Turkish President Tayyip Erdogan would see who Ankara’s reliable ally is, alluding to the United States.

“I hope President Erdogan will see that we are the ally of their past and their future, she said. “They see what Russia is, they see what they’re doing now,” she told reporters in a briefing. She repeated Washington’s call on Ankara to walk away from the purchase of the Russian missile defence system.

Turkey and the United States have been at loggerheads over Ankara’s decision to buy the Russian S-400 systems. Washington has threatened to impose sanctions on its NATO ally Turkey if Ankara refused to drop the weapons.

(This story has been refiled to correct typographical error in headline)