WASHINGTON (Reuters) - The United States, in a sharp shift in tone, wants the United Nations to authorize not just a no-fly zone to aid Libyan rebels but also air strikes against Libyan tanks and heavy artillery, U.S. officials said on Thursday.
The move toward a tougher stance in favor of military action comes after an extended internal debate within the Obama administration over how to stop Libyan leader Muammar Gaddafi's battle to put down a rebellion that has threatened his 30-year reign.
The Libyan opposition has appealed for immediate assistance to prevent the rebel capital of Benghazi from falling to forces loyal to Gaddafi, and the question facing President Barack Obama and other world leaders was whether the action they planned to take would come in time.
U.S. officials said the United States has concluded a "no-fly" zone should be adopted and other measures that go well beyond a no-fly zone, should be taken, including air strikes against Libyan tanks and heavy artillery.
The United States is also seeking U.N. authorization for other steps under consideration, including diverting frozen Gaddafi assets to Libyan rebels for buying weapons and tightening a Libyan arms embargo.
U.S. officials believe the measures could be implemented rapidly to have an immediate impact.
The United States supports international measures in Libya that are "short of boots on the ground," Undersecretary of State William Burns said on Thursday.
Burns also told the Senate Foreign Relations Committee that a no-fly zone over Libya could have "an important, positive, practical" effect, but it was still necessary to consider other measures.
He said Washington is concerned Gaddafi could "return to terrorism and violent extremism" and create turmoil in the Middle East.
Pentagon officials have made clear their wariness of instituting a no-fly zone with U.S. forces already engaged in Iraq and Afghanistan and a massive relief operation under way in Japan.
Any military plan adopted must have active participation by Arab League nations.
"They have to do more than just support it," a senior official said.
Obama has been under pressure from Britain and France to join together in taking tough action against Gaddafi before the moment to do so slips away.
The U.S. ambassador to the United Nations, Susan Rice, said on Twitter that urgent negotiations were continuing at the U.N. Security Council about a Libya resolution.
"US view -- need to take steps beyond no-fly zone to protect civilians," she wrote.
French U.N. Ambassador Gerard Araud said he wanted a vote by 6:00 p.m. EST (2200 GMT) on Thursday.
The former Libyan ambassador to the United States, Ali Aujali, who backs the rebels, appealed for immediate help in a CNN interview.
"President Obama, please, I am asking you for the second or third time, you know Gaddafi, you know what he will do," he said.