NATO launched fresh air raids on the Libyan capital Saturday as Muammar Gaddafi's government said it was ready to withdraw from Misrata and let tribes deal with rebels in the besieged city.
The strikes hit a patch of bare ground opposite Gaddafi's Bab Al-Aziziya residence in central Tripoli and what looked like a bunker. Authorities who took foreign correspondents there said they were "a parking lot" and "sewers".
The strikes were launched after Deputy Foreign Minister Khaled Kaim said Libya's army had been given an "ultimatum" to stop the rebellion in the western city of Misrata, 200 kilometres (120 miles) from Tripoli.
"There was an ultimatum to the Libyan army: if they cannot solve the problem in Misrata, then the people from (the neighbouring towns of) Zliten, Tarhuna, Bani Walid and Tawargha will move in and they will talk to the rebels," said Kaim.
"If they don't surrender, then they will engage them in a fight," he told journalists in the capital.
The announcement is seen as an apparent ploy by the regime to complicate the task of NATO forces trying to take out pro-Gaddafi fighters without harming the civilians, including tribes, they are meant to protect under a UN mandate.
But it is not expected to bring any changes to the front line as many tribesmen already fight as militias or "volunteers" under the banner of the Libyan army.
Misrata has for weeks been the scene of deadly urban guerrilla fighting between rebels and forces loyal to Colonel Gaddafi.
Kaim accused Washington of "new crimes against humanity" after US President Barack Obama authorised deployment of missile-carrying drone warplanes over Libya for what his administration called "humanitarian" reasons.
He also hit out at a senior US senator's visit to Benghazi, the rebel capital in the east, saying the Transitional National Council (TNC) did not represent Libyans and had "no authority on the ground".
John McCain, a Republican senator who lost the presidential race to Obama in 2008, earlier held talks with TNC leaders, urging the international community to arm and recognise the rebel body.
Rebels bogged down in their bid to oust Gaddafi hailed the US decision to deploy armed drones over Libya.
"We hope that this can bring some relief to the people in Misrata," rebel spokesman Mustafa Gheriani told AFP of the rebel-held western city that Gaddafi's forces have pounded for more than six weeks, killing hundreds.
Following Saturday's NATO air strikes near the compound where Gaddafi resides, anti-aircraft fire rang out as ambulance sirens wailed.
Allibya television said the capital was "now the target of raids by the barbaric crusader colonialist aggressor," referring to Western forces.
The official JANA news agency reported two people died in NATO air raids late Friday on the Zintan region southwest of Tripoli where stepped up fighting has taken place with rebels who hold several towns.
NATO warplanes continued to overfly Tripoli on Saturday.
The military alliance says the unmanned drones and their precision would give the coalition forces more options, especially in urban warfare.
"The use of drones will make it easier to target Gaddafi forces in crowded urban areas. A vehicle like the Predator, that can get down lower and can get IDs, will better help us carrying out the mission with precision and care," the NATO official said.
The US military's top officer, meanwhile, said allied air strikes had destroyed 30 to 40 per cent of Gaddafi's forces and noted the conflict was progressing into a stalemate.
"I am sure that NATO forces will continue to attrite the military capability of the regime forces," Admiral Michael Mullen said.
Rebels have complained civilians are being killed in places like Misrata, where entire streets have been pulverised by gunfire, shelling and cluster bombs.
France, Italy and Britain have said they would send military personnel to eastern Libya, but only to advise the rebels on technical, logistical and organisational matters and not to engage in combat.
French President Nicolas Sarkozy has signalled his intent to follow in US Senator McCain's footsteps and visit Benghazi.
On the humanitarian front, the Red Cross warned the situation in Misrata could "rapidly deteriorate further and the lack of basic services such as water, electricity, food and medical care could turn critical."
On Saturday, an aid ship delivered 160 tons of food and medicine to the port city before it evacuated around 1,000 stranded refugees, mostly Nigerians.
Hundreds of Libyan families lined up along the harbour front in hope of getting on board the ship chartered by the International Organisation for Migration, which has already transported 3,100 refugees from 21 countries out of the besieged city.
But Dakir Hussam, a Syrian electrician, expressed his delight at managing to get a place on the Red Star One after witnessing violent clashes. "Gaddafi's men shoot at anything that moves in the city, but they are also suffering a lot," he said, referring to the burial he saw of up to a dozen loyalist fighters this week.
The UN refugee agency says about 15,000 people fled fighting in western Libya into Tunisia in the past two weeks and a much larger exodus was feared.
Massive Libyan protests in February — inspired by the revolts that toppled long-time autocrats in Egypt and Tunisia — escalated into war when Gaddafi's troops fired on demonstrators and protesters seized several eastern towns.
The battle lines have been more or less static in recent weeks, however, as NATO air strikes have helped block Gaddafi's eastward advance but failed to give the poorly organised and outgunned rebels a decisive victory.
Gambia, meanwhile, said it was joining France, Italy and Qatar in recognising the TNC as the sole legitimate body representing Libyan interests, while expelling Tripoli's diplomats.