Nato has carried out its heaviest air strikes against Libya's capital in more than two months of bombing, amid upbeat comments from France and the United States on progress towards ending Muammar Gaddafi's rule.
Six loud explosions rocked Tripoli late on Tuesday within 10 minutes, following powerful strikes 24 hours earlier, including one on Gaddafi's compound, that Libyan officials said killed 19 people and state television blamed on "colonialist crusaders".
French foreign minister Alain Juppe said on Tuesday that the Nato bombing campaign was making progress and should achieve its objectives within months. An alliance official said Tuesday's early strike was "the most concentrated to date".
France, Britain and the United States are leading the air strikes, which started on March 19 after the United Nations Security Council authorised "all necessary measures" to protect civilians from Gaddafi's forces as he sought to crush an uprising against his 41-year rule.
The three countries have declared they will keep up the campaign until Gaddafi leaves power. Juppe's upbeat assessment came after the United States said the Libyan leader's departure was inevitable.
"There are more and more centres of resistance (to Gaddafi), especially in the west," Juppe said during a question and answer session in the French parliament. "Defections are speeding up."
"I can assure you that our will is to ensure that the mission in Libya does not last longer than a few months."
France said this week that it would deploy attack helicopters to ensure more precise attacks against Gaddafi forces embedded among the civilian population of Libyan cities. Britain said on Tuesday it was considering doing the same.
Military analysts said these plans and the intensified bombing of Tripoli reflected growing Western worries that Libya's civil war was dragging on indecisively. But they said the new moves may not be enough to tip the balance quickly.
Boost for rebels While critics argue that Nato has overstepped its mandate, rebels have complained Western forces are not doing enough to break Gaddafi's army.
Gaddafi denies his forces target civilians and says rebels, who control the east of the oil-producing country, are criminals, religious extremists and members of al Qaeda.
The United States bolstered the credentials of the Benghazi-based rebel National Transitional Council as a potential government-in-waiting on Tuesday when a US envoy invited it to set up a representative office in Washington.
Unlike France, Italy and Qatar, the United States has not established formal diplomatic ties with the rebels.
Jordan said on Tuesday it recognised the rebel council as a legitimate representative of Libya's people and planned to open an office in Benghazi.
Libyan news agency Jana said targets hit by Nato on Tuesday included a Tripoli mosque called Nuri Bani, though this could not be independently verified.
A French newspaper reported that Gaddafi was tired of fighting a civil war under constant pressure from Nato bombs, and would step down if allowed to remain in his country.
France Soir, citing "reliable sources, close to Libyan power", said people in Gaddafi's entourage had been holding secret meetings with representatives from Western countries, including France, for weeks.
It said Gaddafi, traumatised by the death of a son and three grandchildren in a Nato raid, was tired of living as a hunted man and spent several hours a day watching Arabic news channels and surfing news on Arab, English and Italian web sites. In his public pronouncements, Gaddafi has vowed to fight to the death.