WASHINGTON — Members of the Senate Foreign Relations Committee grilled top Trump administration diplomats Tuesday on the impact of Turkey’s military incursion in northeast Syria, just as a U.S.-brokered ceasefire was set to expire.

Questioning led by Committee Chairman Sen. James Risch, R-Idaho, and New Jersey Sen. Bob Menendez, the top Democrat, focused on the Trump administration’s hasty withdrawal of troops from northeast Turkey following a phone call between President Donald Trump and his Turkish President Recep Tayyip Erdogan. Following the withdrawal, Turkey began an offensive targeting U.S.-allied Kurdish forces in northeast Syria.

James Jeffrey, the U.S. special representative for Syria and special envoy to the Global Coalition to Defeat ISIS., said Turkey launched its military operation “despite our objections, undermining the defeat ISIS campaign, risking endangering and displacing civilians, destroying critical civilian infrastructure, and threatening the security of the area. Turkey’s military actions have precipitated a humanitarian crisis and set conditions for possible war crimes.”

Under an agreement with the Trump administration, Turkey was expected to move Tuesday from a ceasefire to a halt, a more permanent version of the ceasefire. In exchange, Kurdish forces have withdrawn from the 140-kilomete zone in northeast Syria that Turkey has declared a “safe zone.”

Sen. Marco Rubio, R-Fla., said he did not believe that Erdogan wanted only a “safe zone,” but rather to control a large strategic swath of land in the region.

Menendez pressed Jeffrey on the communication between him and the White House, asking if he was consulted on the removal of U.S. troops from Syria. “I was not consulted,” Jeffrey said.

Members of the committee also focused on the possible resurgence of ISIS. There are roughly 10,000 detained ISIS fighters imprisoned in northern Syria who are guarded by Kurdish forces. “Very few, dozens, have escaped,” said Jeffrey.

Despite the “relatively stable” situation following the ceasefire, Jeffrey said that over 100 Kurds had been killed during the Turkish incursion.

In response to questioning from Democratic Sen. Chris Coons of Delaware, Jeffrey stressed that Trump did not get “rolled” by Erdogan.

“We will need to have some serious conversations with them,” he said, “including on the levying or easing of strong sanctions.”