Fighting rages in Misrata
Tripoli - Fighting raged in the long-besieged rebel-held Libyan city of Misrata on Friday and Muammar Gaddafi's hometown was reportedly hit by Nato, as world leaders said the Libyan leader had to go.
Heavy gunfire and shelling could be heard in Misrata, with sustained exchanges near the centre before nightfall, an AFP photographer reported.
Loud explosions which had been heard since the morning were spaced closer together, he said from the city's hospital.
Rebel checkpoints were seen around a now-abandoned residential area where nests of loyalist snipers were suspected to be active.
The rebels said Gaddafi forces were firing shells and mortar rounds 2km away from the main road, Tripoli Street.
"We want Nato to attack Tripoli Street - there are no civilians there," pleaded one rebel.
Several insurgents claimed Gaddafi's forces were using cluster bombs, which are banned under international law in civilian-populated zones.
AFP could not verify their claims.
Under heavy fire
On Thursday, Misrata came under heavy attack by Gaddafi's forces, who fired dozens of Grad missiles and tank shells that killed at least 13 people and wounded 50, a rebel spokesperson said.
Meanwhile, state news agency Jana said Gaddafi's home town of Sirte was targeted by Nato warplanes on Friday.
"Aggressor colonialist crusaders" launched air raids on Sirte, it said, adding that the town of Al-Aziziya, south of Tripoli, was attacked again after state television reported raids there on Thursday evening.
And rebels fired off barrages of rockets from the edge of the eastern city of Ajdabiya as they advanced towards the key oil refinery town of Brega.
On the diplomatic front, the leaders of Britain, France and the United States said a Libyan future including Gaddafi is "unthinkable," while Russia charged that Natowas exceeding its UN mandate in Libya.
British Prime Minister David Cameron, France's President Nicolas Sarkozy and US President Barack Obama penned a joint article saying Gaddafi's staying on would represent an "unconscionable betrayal" by the rest of the world.
"It is unthinkable that someone who has tried to massacre his own people can play a part in their future government," said the article, which appeared in The Times of London, The Washington Post and French daily Le Figaro.
French Defence Minister Gerard Longuet said that the US, Britain and France are thinking beyond UN Security Council Resolution 1973 - which authorises action to protect Libyan civilians - and now seek regime change.
He admitted on LCI television the statement by the three leaders went beyond the terms of the current UN mandate.
"But I think that when three great powers say the same thing, it's important for the United Nations, and perhaps one day the Security Council will make another resolution," he added.
On Thursday, differences over how to deal with the Libyan crisis began to widen when the BRICS group - Brazil, Russia, India, China and South Africa - urged that "the use of force should be avoided".
Russian President Dmitry Medvedev went further, arguing that Resolution 1973 did not authorise military action of the kind being carried out in Libya by attack jets from Nato and some Arab countries.
Longuet dismissed this, arguing that Russia, China and Brazil "will naturally drag their feet.
"But which of the great countries can accept that that a head of state can resolve his problems in training cannon fire on his own population? No great power can accept that.
"I'd like to see, alongside military action, a political opening so that Libyans can come together to imagine for themselves a future without Gaddafi."
In Berlin, Russian Foreign Minister Sergei Lavrov called for an urgent move towards a political settlement.
"Today, we can see actions that in a number of cases go beyond the mandate of the UN Security Council," he said after talks with Nato foreign ministers.
"We believe it is important to urgently transfer things into the political course and proceed with a political and diplomatic settlement."
"We should have an immediate ceasefire and bring the warring parties to the negotiating table so they can agree on the structure of their own country."
Resolution 1973 calls for a ceasefire, but Gaddafi has relentlessly pursued his campaign to retake territory lost to the rebels.
Nato Secretary General Anders Fogh Rasmussen denied that the air strikes were beyond the scope of the UN resolution.
"I have to stress that in the conduct of that operation, we do not go beyond the text or the spirit" of the resolution, he told a news conference.
Italy insisted that its fighter jets would not bombard Libya, saying Rome was doing enough to support the UN resolution to protect civilian lives.
And Canadian Prime Minister Stephen Harper said his country will not consider increasing its forces until after a May 2 election.
Meanwhile, the European Union and Nato deepened their coordination for a potential EU military mission to deliver urgent humanitarian aid to Misrata, which has been besieged for more than a month, diplomats said.
EU foreign policy chief Catherine Ashton met Nato foreign ministers in Berlin to discuss ties between the two organisations and the situation in Libya.
Any EU mission would have to be coordinated with Nato because the 28-nation alliance has several warships and units of warplanes in the Mediterranean.
In the key crossroads town of Ajdabiya, east of Misrata and on the front line between the rebel-held east and the mainly government-held west, rebels fired off barrages of rockets, an AFP reporter said.
A rebel convoy fitted with big guns and rocket launchers drove westwards past Ajdabiya to see if pro-regime forces had been rolled back by Nato the previous day.
The convoy of pick-up trucks had nosed cautiously westward, past a point that late Thursday was the scene of a brief exchange of rocket and mortar fire with loyalist troops.
They soon afterwards sent off volleys of rockets but received no return fire, leaving the whereabouts of Gaddafi's forces unknown.
Nato warplanes were flying high above and explosions could be heard in the distance but it was unclear whether they were bombings.
Witnesses reported Nato air strikes on pro-Gaddafi armour in the Zintan region of western Libya, amid clashes with rebels who hold several areas and reports from rebels that dhafi troops were trying to cut the road to nearby Yafran.
Rebels said they had lost eight fighters and that another 11 were wounded, and that that had take several prisoners.
"There were air strikes on tanks of Gaddafi loyalists a dozen or so kilometres (seven miles) from Zintan," a town of 40 000 people around 150km southwest of Tripoli, one witness told AFP.
He added that warplanes had been overflying the area all day.