The U.N. Security Council voted Thursday to impose a no-fly zone over Libya and authorize "all necessary measures" to protect civilians from attacks by Moammar Gadhafi's forces, hours after the Libyan leader vowed to crush the rebellion with a final assault on the opposition capital of Benghazi.
The Obama administration was readying plans to enforce the no-fly zone with the help of Arab countries, officials said after the U.N. vote.
President Obama has been buffeted by criticism for not moving more aggressively to help the rebels trying to topple Gadhafi, long counted as among the world's most ruthless dictators.
The vote paved the way for possible international airstrikes on Gadhafi's advancing military and reflected this week's swift reversal of the situation in Libya, where once-confident rebels are now in danger of being obliterated by an overpowering pro-Gadhafi force using rockets, artillery, tanks and warplanes. That force has advanced along the Mediterranean coast aiming to recapture the rebel-held eastern half of Libya.
The resolution, using Libya's official name, establishes "a ban on all flights in the airspace of the Libyan Arab Jamahiriya in order to help protect civilians." It also authorizes U.N. member states to take "all necessary measures to protect civilians and civilian populated areas under threat of attack in the Libyan Arab Jamahiriya, including Benghazi, while excluding a foreign occupation force of any form on any part of Libyan territory."
The vote was 10-0 with five countries abstaining, including Russia and China, which have veto power in the council, along with India, Germany and Brazil. The United States, France and Britain pushed for speedy approval. A veto would have torpedoed the resolution.
In Benghazi, the al-Jazeera satellite TV channel showed a large crowd watching the vote on an outdoor TV projection and bursting into celebration as green and red fireworks exploded in the air.
In Tobruk, east of Benghazi, happy Libyans fired weapons in the air to celebrate the vote.
In contrast, a dentist in the capital of Tripoli condemned the measure. "You are in fact protecting people carrying weapons against the official forces. This is nonsense," said Mohammed Salah, 33.
In an interview broadcast just before the Security Council voted, Gadhafi dismissed its actions. "The U.N. Security Council has no mandate. We don't acknowledge their resolutions," he said. He pledged to respond harshly to U.N.-sponsored attacks. "If the world is crazy, we will be crazy, too," he said.
U.S. officials have said the U.N. authorization for "all necessary measures" provides a legal basis for countries to carry out airstrikes to protect civilians from Gadhafi's forces.
Obama administration officials, who spoke after a closed-door briefing in Congress, said they expected the attempt to ground Gadhafi's air force could begin by Sunday or Monday. The effort likely would involve jet fighters, bombers and surveillance aircraft.
One official said Jordan, Qatar and the United Arab Emirates were among possible participants, in a showing designed to demonstrate that the effort to shield rebels trying to bring down Gadhafi had support from other countries in the region.
William Burns, U.S. undersecretary of state for political affairs, said Gadhafi's forces "have made significant strides on the ground over the course of the last 24, 48 hours taking full advantage of their overwhelming military."
The disclosures came as Secretary of State Hillary Rodham Clinton said in Tunisia that a no-fly zone would include "certain actions taken to protect the planes and the pilots, including bombing targets like the Libyan defense systems."
The details of any military action were unclear, and Air Force Chief of Staff Gen. Norton Schwartz told Congress in public testimony it would take as much as a week to impose a no-fly zone over Libya.
"We had said all along that Gadhafi must go," said British Foreign Secretary William Hague. "It is necessary to take these measures to avoid greater bloodshed."
In Britain, a lawmaker with knowledge of defense matters confirmed that British forces were on standby for airstrikes and could be mobilized as soon as Thursday night.
French Prime Minister Francois Fillon told France-2 Television that if the Security Council approved the resolution France would support military action against Gadhafi within a matter of hours.
The resolution also calls for stronger enforcement of an arms embargo; adds names of individuals, companies and other entities to the list of those subject to travel bans and asset freezes; and requires all countries to ban Libyan flights from landing, taking off or overflying their country.
It also demands that Libya ensure the "rapid and unimpeded passage of humanitarian assistance" and asks U.N. Secretary-General Ban Ki-moon to establish an eight-member panel of experts to assist the Security Council committee in monitoring sanctions.
Russia and China had expressed doubts about the U.N. and other outside powers using force against Gadhafi, a view backed by India, Brazil and Germany, which also abstained.
German U.N. Ambassador Peter Wittig expressed fear that using military force could lead to "the likelihood of large-scale loss of life."
Despite the lack of consensus, U.S. Ambassador Susan Rice said: "Today the Security Council has responded to the Libyan people's cry for help."