The former head of U.S. Special Operations Command warned that the drawdown of American troops from northern Syria could allow ISIS militants to regroup and exploit the fighting between different factions to regain territory.

Recently retired four-star General Raymond Thomas, who led the United States Special Operations Command for three years, said the conditions created by the recent American withdrawal could pave the way for a resurgence of ISIS.

"I think they'll have a great opportunity to do that, because you've got all the precursors that existed before the Assad regime. Representative government, or not, in Iraq," Thomas said on "Face the Nation" Sunday. "So there'll be a void, and I think they will rally. These are resilient adversaries. We've done nothing to knock down the ideology, and I think they'll see this is certainly a respite if not an opportunity to have a resurgence."

After President Trump ordered an unexpected withdrawal of the U.S. troops tasked with preventing fighting between Turkey and U.S.-allied Kurdish forces in northern Syria, the Turkish military launched a full-blown offensive with the help of Arab militants to take the land held by the Kurds, which the government in Ankara has long accused of fostering discord and terrorism within Turkey.

The swift Turkish-led incursion prompted Mr. Trump to order a "deliberate withdrawal" of all of the approximately 1,000 U.S. troops in northern Syria — a decision which elicited strong bipartisan condemnation from lawmakers who accused the White House of abandoning the Kurdish forces that were instrumental in U.S. efforts to defeat the territorial ISIS caliphate.

Amid the pressure from Congress, the White House on Thursday brokered what it called a temporary ceasefire that required Turkey to end hostilities for five days to give Kurdish forces a chance to abandon their positions from areas Ankara is looking to occupy.

The brief ceasefire, however, remains fragile and Turkish President Recep Tayyip Erdoğan has vowed to resume the offensive if the Kurdish withdrawal does not come to fruition.

Asked if the Kurds have been effectively asked to surrender by the American-backed deal, Thomas replied, "I think they are being asked to survive."