The U.S. plans to withdraw all of its troops from Syria, multiple news outlets reported Wednesday, citing anonymous defense officials. About 2,000 U.S. troops are currently in the northeastern part of the country, near the Turkish border.

In a tweet Wednesday morning, President Trump did not mention the troop withdrawal, but seemed to refer to it obliquely. "We have defeated ISIS in Syria, my only reason for being there during the Trump Presidency," he wrote.

On both Capitol Hill and in the Pentagon, the reports stirred confusion as officials tried to understand who had ordered the withdrawal, NPR's Tom Bowman reported.

U.S. troops have been in Syria since late 2015. The U.S. and its allies have largely been successful in their campaign to defeat ISIS and capture territory it claimed as its "caliphate."

In a statement from Press Secretary Sarah Sanders on Wednesday morning, the White House would neither confirm nor deny the reports of the troop withdrawal:

"Five years ago, ISIS was a very powerful and dangerous force in the Middle East, and now the United States has defeated the territorial caliphate. These victories over ISIS in Syria do not signal the end of the Global Coalition or its campaign. We have started returning United States troops home as we transition to the next phase of this campaign. The United States and our allies stand ready to re-engage at all levels to defend American interests whenever necessary, and we will continue to work together to deny radical Islamist terrorists territory, funding, support, and any means of infiltrating our borders."

A troop withdrawal would be a reversal of policy discussed as recently as this month by Defense Secretary James Mattis, who said that after the defeat of ISIS, U.S. forces would remain in Syria to prevent a resurgence of the terrorist group.

Northern Syria, where the U.S. troops are located, is under Kurdish control. The U.S. has been allied with the Kurds in the battle against ISIS, but not in their fight against Assad.

Trump and other U.S. officials have been critical of the Assad regime, but the U.S. has not made sustained efforts to topple his regime. With support from Russia, Assad and his backers have essentially won the war, and now seek to extend their rule over the parts of the country they don't yet control.

Turkey considers the Kurds to be a terrorist group, and has troops posted in Syria along the Turkish border. With U.S. troops gone, Turkey would likely have free reign over the area. Trump recently spoke by phone with Turkish president Recep Tayyip Erdogan about Syria.

On Twitter, Sen. Lindsey Graham, R-S.C., voiced his displeasure with a troop withdrawal plan.

"Withdrawal of this small American force in Syria would be a huge Obama-like mistake," Graham tweeted. "With all due respect, ISIS is not defeated in Syria, Iraq, and after just returning from visiting there — certainly not Afghanistan. President @realDonaldTrump is right to want to contain Iranian expansion. However, withdrawal of our forces in Syria mightily undercuts that effort and put our allies, the Kurds at risk."

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