Tripoli/London: Forcing rebels to retreat, Libyan forces on Tuesday struck back at them. The rebels were advancing towards Muammar Gaddafi's hometown of Sirte as world leaders in London vowed to intensify air strikes to stop his "murderous attacks" on civilians.

Using rockets and tanks, Gaddafi's forces pushed back the rebels closing in on Sirte even as coalition forces pounded his arsenal.

Al Jazeera said Gaddafi's forces shelled the pro-democracy forces heading west on the main coastal highway. The rebels were pushed out of Bin Jawad, about 150 km east of Sirte, the Arab channel said but there was no independent corroboration.

Reports reaching here also said that Gaddafi's troops attacked the rebel-held Misurata, 214 east of Tripoli, forcing the outgunned rebels to fall back.

Libyan army officials claimed that their forces had recaptured and liberated Misurata and declared a ceasefire on the western front. However, rebel sources said street fighting was on in the centre of the town.

Helped by heavy strikes by coalition forces, the rebels were reported to have regrouped in Harawa, 60 km from Sirte to capture the town of Nawfaliyah as the uprising against Gaddafi's 41-year-old rule entered the sixth week.

Rebels used mortars and heavy machine guns to smash through Government forces, defences at Nawfaliyah but were meeting stiff resistance from Gaddafi's troops, the Arab channel said.

Bombardments of the road between Bin Jawad and Nawfaliyah sent the rebels fleeing, media reported.

NATO and US warplanes pounded tanks and heavy guns of Gaddafi's forces. For the first time, US media reports said Americans used the AC-130S and A-10 attack aircraft to carpet bomb government troops.

The aircraft which fly low and slow over the battle field were deployed only after a week of allied airstrikes, which decimated Gaddafi's airforce.

These aircraft armed with heavy machine guns and cannons raked the ground to flush out dug-in troops and convoys in closer proximity to civilians. The planes have been deployed to step up pressure on Libyan ground forces.

World leaders from about 40 countries at the London meeting said the allied air strikes would continue until Gaddafi "stops his murderous attacks."

Clinton asks Gaddafi to leave power

Addressing the meeting, Secretary of State Hillary Clinton implored the world to speak with a single voice to Gaddafi and tell him to leave power.

Clinton said that Libya "belongs not to a dictator, but to its people." The allied air strike would go on in Libya until Gaddafi met UN terms and stopped attacking civilians.

She said that all of the countries represented at the gathering in London "must speak with one voice in support of a transition that leads to a brighter future for Libya," the Fox News reported.

British Prime Minister David Cameron accused Gaddafi of shooting and starving his opponents into submission. "We are all here in one united purpose, which is to help the Libyan people in their hour of need."

UN Secretary General Ban Ki-moon, EU and NATO leaders, Arab League and leaders from African Union joined the talks to ratchet up pressure on Gaddafi and to chalk out an agreement on Libya's future.

Ahead of the meeting, President Barack Obama vigorously defended American military intervention in Libya, saying failure to act would have carried a far "greater price" for the US and also led to a "slaughter" of civilians in the north African nation.

Noting that the US has an important "strategic interest" in preventing Gaddafi from overrunning those who oppose him, Obama also declared, "we have stopped Gaddafi's deadly advance."

At the same time, Obama in his first address to the nation since launching cruise missiles and airstrikes 10 days ago ruled out targeting Gaddafi citing the Iraqi experience, warning that trying to oust him militarily would be a costly mistake.

Britain formally recognised Libya's rebel leadership as the country's legitimate government, becoming the third country after France and Qatar to take this step.

Cameron and French President Nicolas Sarkozy issued a joint statement supporting the interim National Transitional Council.

The statement came as a Downing Street spokesman confirmed diplomats had made contact with the council.

British foreign Secretary William Hague said he wanted Gaddafi to leave power and face trial at the International Criminal Court.

Italian Foreign Minister Franco Frattini said several countries planned to put forward a deal which would propose a ceasefire, exile for Gaddafi and a framework for talks between Libya's tribal leaders and opposition figures on the country's future.

The London meet will also decide on the scope of NATO-led coalition airstrikes and to more clearly define the extent of cooperation between Libya's opposition groups and International Military Commanders.

As the international leaders started assembling in London, Gaddafi in a letter addressed to them called for an end to what he called as "barbaric offensive" against Libya, likening it to Hitler's invasion of Europe and bombing of Britain in the World War-II.

Gaddafi hits back at West

"Stop your barbaric, unjust offensive on Libya. Leave Libya to Libyans", Gaddafi said in a letter to the leaders meeting in London, a copy of which was released by official Jana news agency.

Gaddafi in his letter said he will "accept any decision taken by the African Union".
"How could you attack those who are fighting al Qaeda", he asked.

The London conference, hosted by the British Foreign Secretary, included representatives of about 40 countries and international organisations, including UN Secretary General, African Union chairman Jean Ping, Qatari Prime Minister, foreign ministers from Iraq, Jordan, UAE and Morocco besides Clinton and foreign ministers from across Europe.

The Arab League, Lebanon and Tunisia will also be represented. Russia will not be represented, as its leaders have protested at what they see as an abandonment of the UN resolution in favour of a move towards formal regime change.