WASHINGTON (Reuters) - Four 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.

The bill would prevent 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 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 becomes 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.

Other lawmakers argued it was in the U.S. national security interest to get more involved in Syria.

"This is about looking at the possibility of a failed state in which terrorist actors already present within Syria in this fight can launch attacks against our allies, and potentially against the United States," Democrat Robert Menendez of New Jersey, chairman of the Senate Foreign Relations Committee, told reporters.

After months of equivocating, Obama decided a week ago to provide military aid to rebels trying to overthrow Syrian President Bashar al-Assad, citing Assad's government's use 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, a former senator, has been on Capitol Hill at least twice this week to make the administration's case to lawmakers.

On Tuesday he had a classified briefing for House of Representatives leaders from both parties and committee chairmen.

On Thursday Kerry conducted at least three briefings: one for the House Intelligence Committee, a second for the Senate Foreign Relations Committee and a third for other senators.
Many members of Congress, particularly in the Republican-controlled House, remain deeply sceptical about plans to arm the rebels, questioning the cost when other programs are being cut and worrying that U.S. weapons could fall 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.

Last month the Senate Foreign Relations Committee voted 15-3 in favour of a bill to provide lethal aid to the Syrian opposition. That measure has not yet 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.