BENGHAZI, Libya – The UN Security Council on Thursday cleared the way for air strikes to halt Moamer Kadhafi's assault on embattled rebels in Libya, sparking celebratory gunfire in the city of Benghazi under threat of imminent attack.

Making the first raids possible within hours, the Security Council approved a resolution permitting "all necessary measures" to impose a no-fly zone, protect civilian areas and impose a ceasefire on Libyan leader Kadhafi's military.

The vote passed 10-0 with five abstentions in the 15-member Council. Permanent members China and Russia were among those abstaining, but did not use their veto power.

Diplomats indicated that air strikes from a coalition led by Britain, France and the United States could be imminent as Kadhafi's troops close in on the rebel stronghold of Benghazi. However, the resolution rules out sending foreign ground troops.

Celebratory gunfire rang out across Benghazi moments after the UN Security Council vote.

Gunfire crackled across the night sky as preachers at mosques in the Mediterranean city of eastern Libya took to loudspeakers shouting "God is greatest, God is greatest."

Tracer bullets streaked across the night sky like fireworks and anti-aircraft fire punctuated the sound of cars honking their horns.

Kadhafi, in a televised address, warned just hours before the vote in New York that his troops would launch an assault on Benghazi on Thursday night and show "no mercy."

"We will chase the traitors from Benghazi," he told his troops. "Destroy their fortifications. Show them no mercy. The world needs to see Benghazi free."

The Libyan leader also said "those who surrender and throw down their arms will be saved."

The rebel command of the city of Benghazi, meanwhile, ordered fighters to man artillery posts and missile batteries after the announcement of the imminent assault, rebel radio reported.

Kadhafi spoke shortly after the defence ministry ratcheted up the odds by saying "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.

France's foreign minister signalled that military strikes could quickly follow UN approval, telling reporters that his country was ready to carry out any resolution.

"France is ready, along with others, to put in action the Security Council resolution, including in this field," he said before the vote.

Qatar and United Arab Emirates could be among the Arab nations to join any coalition that takes action against Kadhafi's regime, the Arab League's UN representative said.

While the talks were under way at the United Nations, insurgents claimed they had shot down warplanes trying to bomb Benghazi and disputed claims of territorial gains by Kadhafi forces.

The latest developments came amid claims and counter-claims about the progress of fighting, which could not be independently confirmed.

State television said loyalists were on the outskirts of Benghazi, the major Mediterranean city in the east and seat of the month-old rebellion against Kadhafi's iron-fisted four-decade rule.

Allibya television said "the town of Zuwaytinah is under control (of loyalists) and armed forces are on the outskirts of Benghazi."

A rebel spokesman told AFP by telephone: "The Kadhafi forces tried to carry out an air raid on the city but our anti-aircraft defences repulsed the offensive and two planes were shot down."

Libyan television also said loyalists had overrun the rebel bastion of Misrata, 200 kilometres (125 miles) east of Tripoli, but that was denied by a rebel spokesman there.

"We still control the city, even its outskirts. Kadhafi is mobilising his forces a few kilometres away," the spokesman said by phone.

He said 18 people, including three civilians, were "martyred" in fierce fighting on Wednesday and that "we inflicted huge losses to the Kadhafi forces, including 60 people killed."

A witness in the western town of Zintan said rebel fighters there were bracing for an attack.

As uncertainty reigned over the situation on the ground, aid agencies on Egypt's border with Libya braced for an onslaught of refugees if Kadhafi prevails.

"If Benghazi is taken, we are expecting 40,000 to 100,000 people, and we are not ready," said Andrea Oess, of Swiss Humanitarian Aid.

Elsewhere in the Middle East, Bahrain rounded up dissidents Thursday as the United Nations warned of "shocking and illegal" abuses in Bahrain where the US-backed Sunni Muslim rulers are waging a bloody crackdown on Shiite-led protesters.

Five hardline Shiite activists and one Sunni were arrested during the night, a parliamentarian from the Shiite opposition alliance said, after a day of violence that left five dead in the Sunni-ruled kingdom.

But the opposition vowed to press on with "peaceful" pro-democracy demonstrations, calling for protests after the Muslim weekly prayers on Friday and sit-in actions on Saturday.