After a morning of fighting in the wake of Thursday’s cease fire announcement, Kurdish fighters on Friday started retreating south of the 20-mile buffer zone in northern Syria that Turkey had demanded, Turkish authorities said.

Defense Secretary Mark Esper, meanwhile, said US troops were continuing their withdrawal from northern Syria, and that no US ground troops would participate in enforcing the cease-fire that Vice President Mike Pence announced Thursday in Ankara.

“The force protection of our service members remains our top priority and, as always, U.S. forces will defend themselves from any threat as we complete our withdrawal from the area,” Esper told reporters.

As fighting continued earlier Friday near the Turkish-Syrian border, President Trump minimized the situation and defended the temporary cease-fire deal the US cut with Turkey’s President Recep Erdogan.

“I just spoke to President Erdogan. Turkey, we’re doing very, very well with Turkey. We have ISIS totally under guard. turkey is also … they are watching over everything,” Trump said at the White House.

“So you have the Kurds who were dealing with and are very happy about the way things are going, I must say, the Kurds, and you also have the Turks watching, so we are [keeping] ISIS under control.

Shelling could be heard at the border on Friday morning despite the five-day cease-fire, and Washington revealed that the deal covered only a small part of the territory Ankara aimed to seize.

Turkey’s military stormed into Kurdish held Syrian territories last week after Trump said he would move US forces from the region.