BY JULIA MANCHESTER, The Hill

Defense Secretary James Mattis said on Sunday that Turkey warned the U.S. before it launched airstrikes in northern Syria against the U.S.-supported Kurdish militia. 

”Turkey was candid,” Mattis said, according to Reuters.
 
”They warned us before they launched the aircraft they were going to do it, in consultation with us,” he continued. 
 
“And we are working now on the way ahead. We’ll work this out.”
 
Turkish ground forces descended upon the Afrin region of northern Syria on Sunday and pounded surrounding areas with artillery fire and airstrikes. 
The strikes are aimed at the U.S.-backed YPG, a Syrian-Kurdish militia that Turkey considers to be a terrorist group. 
 
The State Department urged Turkey to “exercise restraint” to avoid civilian casualties.  
 
Turkey’s Deputy Prime Minister and government spokesman Bekir Bozdağ said last week that Turkey warned the U.S. it would take action in the region if the U.S. continued to aid Kurdish fighters in the area.
 
Secretary of State Rex Tillerson responded, saying action in the area had been misinterpreted and the U.S. is only looking ”to ensure that local elements are providing security to liberated areas.”