WASHINGTON D.C. – Rep. Barbara Lee (D-CA) introduced legislation on Friday that would prevent funding for U.S. boots on the ground in Syria as the fight against the Islamic State in the city of Raqqa is intensifying, including the recent deployment of U.S. Marines and Army Rangers.

“The bill I am introducing today prohibits the Department of Defense from funding any attempt by the administration to expand our presence in Syria by putting U.S. combat boots on the ground,” Rep. Barbara Lee (D-Calif.) explained in a statement to The Hill.

“It is our constitutional duty as members of Congress to place a check on the executive branch in matters of war and peace,” Lee said.

Lee was the only lawmaker who voted against the authorization for the use of military force (AUMF) in the days following the Sept. 11, 2001, terrorist attacks that killed 3,000 people. The AUMF has given ongoing authority to the U.S. military to continue to fight radical Islamic terror around the globe in all of its incarnations, including the Islamic State in Syria.

Secretary of Defense Jim Mattis, a retired United States Marine Corps General who served as the 11th Commander of the United States Central Command and has experience in the Middle East, Northeast Africa, and Central Asia, said during his confirmation hearing that the campaign to retake Raqqa should be accelerated.

On Thursday, Gen. Joseph Votel, commander of U.S. Central Command, confirmed the deployment in a hearing with the Senate Armed Services Committee, The Hill reported.

“Our intention here with this — and this fell within the authorities that are provided to me right now — was to ensure that we had redundant capable fighters support on the ground to support our partners and ensure that we could take advantage of opportunities and ensure the continuing progress that we’ve been seeing,” Votel said.

U.S. forces in Syria total 400 in addition to the 500 U.S. military personnel deployed during the Obama administration.

Lee’s bill would bar the Pentagon from funding ground combat operations in Syria or hire a private security firm to do the same.

The bill includes exceptions to “protect, rescue or remove” U.S. personnel, The Hill reported.

Lee also attempted to impose these restrictions in the form of an amendment to the defense spending bill passed by the House on Wednesday, but the House Rules Committee blocked the amendment, The Hill reported.