Four U.S. senators introduced legislation on Thursday that would bar President Barack Obama from providing military aid to Syria's rebels, saying the administration has provided too little information about what they see as a risky intervention.
Introduced as Obama's administration pushes Congress to support its plan to arm the Syrian opposition, the bill would bar the Department of Defense and U.S. intelligence agencies from using any funds to support military, paramilitary or covert operations in Syria, directly or indirectly.
The measure would not affect humanitarian aid.
The bill's sponsors - Democrats Tom Udall of New Mexico and Chris Murphy of Connecticut and Republicans Mike Lee of Utah and Rand Paul of Kentucky - expressed doubts about Washington's ability to ensure weapons will not fall into the wrong hands, and called for debate in Congress before the United States become more involved in Syria's civil war.
"The president's unilateral decision to arm Syrian rebels is incredibly disturbing, considering what little we know about whom we are arming," Paul said in a statement.
After months of equivocating, Obama decided a week ago to provide military aid to the forces trying to overthrow Syrian President Bashar al-Assad, having obtained proof that Assad's government had used chemical weapons in the two-year-long conflict.
The administration has since been working to win more support in Congress for the plan. Secretary of State John Kerry has been on Capitol Hill at least twice this week briefing members of the House of Representatives on Syria.
On Tuesday, he and other officials had a classified briefing for leaders from both parties and committee chairmen from the House of Representatives.
On Thursday, Kerry and other officials briefed members of the House intelligence committee and the Senate Foreign Relations Committee.
Many members of Congress, particularly in the Republican-controlled House, remain deeply skeptical about plans to arm the rebels, questioning the cost when other programs are being cut and raising concerns about the risk of U.S. weapons falling into the wrong hands.
Others have been pushing for military aid for months, with some senators in particular denouncing Obama for his failure to intervene in a conflict in which more than 90,000 people have been killed.
The Senate Foreign Relations Committee voted 15-3 on May 21 for a bill to provide lethal aid to the Syrian opposition. That measure has not gone to the full Senate for a vote.
Paul, Murphy and Udall were the three members of the foreign relations panel who voted against that bill.