The U.N. Security Council passed a resolution that authorizes member states to use "all necessary measures" to deter forces loyal to Libyan leader Moammar Gadhafi.
Western members of the military coalition enforcing a no-fly zone over Libya are debating whether the language of the resolution authorizes regime change or arming rag-tag rebel fighters.
British Prime Minister David Cameron said Wednesday that the "legal position is clear" meaning assistance could theoretically go to opposition forces in Libya, something echoed by U.S. Secretary of State Hillary Clinton.
U.S. Rep. Ileana Ros-Lehtinen, R-Fla., chairwoman of the House Foreign Affairs Committee, said that Washington's support for opposition forces needed some clarification.
"There are reports that some opposition figures have links to al-Qaida and to extremist groups that have fought against our forces in Iraq," she said during hearings Thursday. "My constituents are asking me: Just who are we helping and are we sure that they are true allies who won't turn and work against us?"
But the White House fended off allegations that Libyan rebels were getting additional support.
Jay Carney, a spokesman for U.S. President Barack Obama, said in a statement that Washington was "reviewing options" in Libya.
"No decision has been made about providing arms to the opposition or to any group in Libya," he said. "We're not ruling it out or ruling it in."