Two members of the Senate Foreign Relations Committee criticized the Obama administration Monday for its handling of U.S. military involvement in Libya and called for a greater congressional role in the decision-making process.

Sen. James Webb (D-Va.), who recently announced he is not running for reelection in 2012, said Monday that President Obama has not yet provided clarity on the U.S. mission in Libya.

“We have a military operation that’s been put into play, but we do not have a clear diplomatic policy or a clear statement of foreign policy that’s accompanying this military operation,” Webb said on MSNBC. He added that the United States also lacks information on Libya’s opposition forces and that Congress has not been given the chance to debate whether the U.S. military should have gotten involved.

“We have not had a debate, and I know that there was some justification put into place because of concern for civilian casualties, but this isn’t the way that our system is supposed to work,” Webb said.

Meanwhile, Sen. Richard G. Lugar (R-Ind.), who had previously criticized Obama on Libya, reiterated Monday that he believed the mission in Libya has not yet been made clear.

“No, I do not understand the mission because as far as I can tell in the United States, there is no mission,” Lugar told CNN’s John King.

On whether the White House has provided answers to any of the lingering questions on Libya, Lugar responded, “Well, there is no answer. There simply is the thought that the president gave to congressional leaders on Friday, that no boots on the ground, no aircraft over. And he said it’s days, not months. Now, that’s not an answer to any of these questions.”

National security adviser Tom Donilon, traveling Monday with President Obama in Brazil, defended the administration’s actions.

“First of all, Senator Lugar was involved in the briefing at 12:30 p.m. on Friday with the president,” Donilon said. “And that kind of consultation is absolutely important and we’ll continue to do that. . . . We take on that responsibility for keeping the Congress fully informed as to what we are pursuing.”

Donilon added that “it is absolutely important to have great clarity” on what the administration’s military actions are, “and I think that we have done that.”

Webb and Lugar are not the first lawmakers to offer recent criticism of the administration’s handling of Libya. Most, though, have been in the House, while Lugar and Webb are two prominent voices in the Senate on foreign relations.

Senate Majority Whip Richard J. Durbin (D-Ill.) also weighed in on the crisis late Monday, with comments more supportive of the administration.

“With the full and unprecedented backing of the Arab League and the United Nations, U.S. forces, along with our allies, are enforcing a no-fly zone over Libya,” Durbin said. “I support this limited, international action. I also agree with President Obama: No U.S. ground forces should be used in this operation, and it must remain limited in scope and duration.”

Video of Lugar’s appearance follows: