The US-led coalition fighting ISIS has told its local Syrian allies that they must be exclusively focused on fighting ISIS and not fight the Syrian regime, a directive that prompted one rebel group to depart a joint coalition base in Southern Syria, several coalition and US defense officials told CNN.

“The coalition supports only those forces committed to fighting ISIS,” coalition spokesman US Army Col. Ryan Dillon told CNN.

But one US-backed group which calls itself “the Shohada Al Quartyan” has balked at the restriction, opting to leave the base to carry out independent operations against Syrian regime troops several US and coalition officials told CNN. The officials added that other local allies remain at the garrison and continue to cooperate with coalition advisers.