Fewer than 1,000 U.S. troops will remain in Syria with a continued mission of defeating ISIS, Chairman of the Joint Chiefs of Staff Gen. Mark Milley said Sunday.

“The footprint will be small, but the objective will remain the same: the enduring defeat of ISIS,” Milley said in an interview on ABC's “This Week.”

ABC’s Martha Raddatz questioned Milley on the number of troops expected to stay in Syria, noting that American troops have remained in the region even as President Trump has said he wanted the 1,000 to leave.

COMING UP: Joint Chiefs Chair Gen. Mark Milley sits down with @martharaddatz and says there are "still" ISIS fighters in Syria: "Unless pressure is maintained...there is a very real possibility that conditions could be set for a reemergence of ISIS." https://t.co/ioOTF1c8I7 pic.twitter.com/CsJn1WrKk5 — This Week (@ThisWeekABC) November 10, 2019

“We’re staying in the south, we’re staying staying in the east with some of our service members guarding those oil fields. If I do my math, and look at the new troops going in and those going out, it could be more than 700 who remain,” Raddatz said.

Milley responded that there will be fewer than 1,000 troops remaining “for sure” and estimated that number would be around 500 to 600.

“It’s in that area, but we’re not going to go into specific numbers because we’re still going through that analysis right now,” he added. ADVERTISEMENT

It’s important for a U.S. presence to remain to ensure there is not a reemergence of ISIS after a U.S. raid last month led to former ISIS leader Abu Bakr al-Baghdadi’s death, he said.

“There are still ISIS fighters in the region and unless pressure is maintained, unless attention is maintained on that group, then there's a very real possibility that conditions can be set for reemergence of ISIS,” Milley said.

Before the raid, Trump had announced troops would be leaving northern Syria ahead of a Turkish offensive against Kurdish forces in the area. U.S. troops had been in the region assisting allied Kurdish forces.

Trump later said a “small” number of troops will remain in Syria, after fierce criticism from Republicans and Democrats.