The White House would need an OK from Congress to use military force in Syria under a defense spending bill in the Senate.
The bill cleared the Senate Appropriations Committee Thursday. It would spend nearly $600 billion on the military, with nearly $78 billion for the war in Afghanistan.
Lawmakers added the requirement on Syria before the bill passed.
Democrat Tom Udall of New Mexico is the amendment's sponsor. Udall sought to bar defense dollars from going to any action in Syria in violation of the War Powers Act. That's a Vietnam-era law requiring the president to obtain a resolution from Congress.
The bill also includes nearly $4.5 billion for shortfalls in military readiness.