WASHINGTON — Top Republican lawmaker John Boehner on Thursday hinted at a potential freeze of funds for military operations in Libya, saying the White House had failed to justify US involvement.

Influential US senators meanwhile voiced their support for a bipartisan resolution at odds with such a move that would authorize limited American military operations against Moamer Kadhafi's regime.

Democratic Senator John Kerry said the United States is not at war with Libya and that the proposed Senate resolution would clarify US involvement and authorize limited military action.

"I've said since the beginning that I didn't believe that the kind of action that we're engaged in there requires our authorization," said Kerry, who serves as chairman of the Senate Committee on Foreign Relations.

"But I've also always said as a member of Congress that we're better off when the Congress joins the administration," he told reporters.

Kerry said the resolution would "probably" be taken up by his committee next week, adding: "We're prepared to bring something to the floor."

In the face of Republican criticism, the White House insisted in a 30-page report this week that the current US military action in Libya was legal.

It has argued that US participation in the NATO-led assault on Kadhafi's forces does not require congressional authorization because the United States is only playing a "supporting role" in the campaign.

The report further noted that the use of force was being used solely to protect civilians and to enforce a no-fly zone and an arms embargo, and that the intervention did not involve US ground troops or "sustained fighting."

But Boehner, speaker of the Republican-controlled House of Representatives, said he was not satisfied with those arguments.

"The White House says there are no hostilities taking place. Yet we've got drone attacks under way; we're spending $10 million a day; we're part of an effort to drop bombs on Kadhafi's compounds," he told reporters.

"It just doesn't pass the straight face test, in my view, that we're not in the midst of hostilities."

When asked what specific action he might take, Boehner said: "The House has options. We're looking at those options, and my guess is that next week we may be prepared to move on those options.

"But the ultimate option is the House, in fact the Congress, has the power of the purse. And certainly that is an option as well."

Republican Senator John McCain, who has co-sponsored the Senate resolution, has said that limited activities in Libya should be authorized but that the president should also submit a description of US policy objectives and consult regularly with lawmakers.

Lawmakers have said the White House did not seek their approval for US involvement in Libya as set out in the 1973 War Powers Resolution, which requires direct, offensive warfare to be endorsed by Congress.

"It's been four weeks since the president has talked to the American people about this mission, and I think it's time for the president to outline to the American people why we are there, what the mission is and what our goals are, and how do we exit this," Boehner said.