Security Council imposes a no-fly zone over Libya and authorises "all necessary measures" to protect civilians.
The United Nations Security Council (UNSC) has backed a resolution authorising a no-fly zone over Libya and "all necessary measures" - code for military action - to protect civilians.
Ten of the council's 15 members voted in favour of the resolution on Thursday, while Russia, China, Germany, India and Brazil abstained.
France said on Friday morning that military action in Libya would come "rapidily ... within a few hours", but did not specify the targets or in what form the action would come.
However officials in the US and Britain have suggested that military intervention would not begin until Sunday or Monday. The NATO military alliance is also due to meet later on Friday to discuss its response to the resolution.
France said on Friday morning that military action in Libya would come "rapidily ... within a few hours", but did not specify the targets or in what form the action would come.
However officials in the US and Britain have suggested that military intervention would not begin until Sunday or Monday. The NATO military alliance is also due to meet later on Friday to discuss its response to the resolution.
Despite choosing not to use its veto to block the resolution, China on Friday expressed serious concerns about imposing the no-fly zone.
"We oppose the use of military force in international relations, and have serious reservations about some of the content of the resolution," Jiang Yu, a foreign ministry spokeswoman, said in a statement.
Turkey on Friday also voiced concern over military intervention, calling for an immediate ceasefire in Libya instead.
But no votes were recorded against the resolution, which was co-sponsored by France, Britain, Lebanon and the United States.
Under the no-fly zone, only military aircraft are forbidden to fly in Libyan airspace. It exempts commercial and humanitarian flights.
In Benghazi, the main opposition stronghold, a large crowd watching the vote on an outdoor TV projection burst into celebration and green and red fireworks filled the air.
Reporting from Benghazi, Al Jazeera's Tony Birtley said the city had been given new buoyancy. "They can go back into this fight with renewed vigour, with renewed hope," he said.
James Bays, Al Jazeera's correspondent in the eastern city of Tobruk, said the sound of gunfire rang out through the night. "Guns were not being fired in anger, but in celebration," he said.
"This is what they have been waiting for, they have been calling for a no-fly zone from the UN ... people here are buoyed by the news."
However, Bays added that it was "worth injecting a note of caution" into the current excitement, as Gaddafi's troops were still standing firm.
His forces have reportedly begun a heavy bombardment of the rebel-held town of Misurata, the last big opposition stronghold in western Libya.
'We will be crazy too'
His forces have reportedly begun a heavy bombardment of the rebel-held town of Misurata, the last big opposition stronghold in western Libya.
'We will be crazy too'
The UN resolution came just a few hours after Muammar Gaddafi, the embattled Libyan leader, warned residents of Benghazi that his forces would show "no mercy" in an impending assault on the city.
"The matter has been decided ... we are coming," he said in a radio address on Thursday.
The Libyan leader called pro-democracy fighters in Benghazi "armed gangsters" and urged residents to attack them, saying: "You all go out and cleanse the city of Benghazi.
"We will track them down, and search for them, alley by alley, road by road ... Massive waves of people will be crawling out to rescue the people of Benghazi, who are calling out for help, asking us to rescue them. We should come to their rescue."
In an interview broadcast just before the Security Council voted on the resolution, Gaddafi dismissed the body's actions.
"The UN Security Council has no mandate. We don't acknowledge their resolutions," he told the Portuguese public Radiotelevisao Portuguesa.
He pledged to respond harshly to UN-sponsored attacks. "If the world is crazy, we will be crazy too," he said.
Speaking to reporters in Tripoli after the vote, Khalid Kaim, the Libyan deputy foreign minister, took a conciliatory tone, offering to negotiate a ceasefire with the rebels.
"We are ready for this decision [a ceasefire] but we require an interlocutor to discuss how to implement it," Kaim told a news conference.
"We discussed last night with the UN envoy [for Libya, Jordan's Abdul Ilah Khatib] and asked legitimate questions on the application of a ceasefire," he said.
Kaim indicated that Libya would "react positively to the UN resolution, and we will prove this willingness while guaranteeing protection to civilians."
Susan Rice, the US ambassador to the UN, said "This resolution demands an immediate ceasefire and a complete end to violence and attacks against civilians.
"The security council has authorised the use of force, including enforcement of a no-fly zone to protect civilians and civilian areas targeted by Colonel Gaddafi, his intelligence and security forces and his mercenaries," Rice said.
However the UN resolution rules out sending foreign ground troops.
Earlier the Libyan defence ministry warned that "any military operation against Libya will expose all air and maritime traffic in the Mediterranean to danger."
"Any civilian or military moving traffic will be the target of a Libyan counter-offensive," the official Jana news agency quoted the defence ministry spokesman as saying.