Protesters take part in an anti-Gadhafi demonstration outside the hotel where representatives of the African Union were meeting leaders of Libya's rebel leadership in Benghazi, April 11, 2011. [Photo/Agencies]

TRIPOLI - An African Union plan to halt Libya's civil war collapsed, and rebels said the increasingly bloody siege of the city of Misrata by Muammar Gadhafi's troops made talk of a ceasefire meaningless.

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The Red Cross said it was opening a Tripoli office and would send a team to Misrata to help civilians trapped by fighting, but one of Gadhafi's ministers warned any aid operation involving foreign troops would be seen as a declaration of war.

Rebel leader Mustafa Abdel Jalil said after talks with the AU delegation in Benghazi in the rebel-held east on Monday:

"The African Union initiative does not include the departure of Gadhafi and his sons from the Libyan political scene, therefore it is outdated." Libyan leader Muammar Gadhafi's son Saif quickly dismissed the idea of his father stepping down.

"We want new blood, that's what we want for Libya's future. But to talk of (Gadhafi) leaving, that's truly ridiculous," he told French news channel BFM TV.

"If the West wants democracy, a new constitution, elections, well, we agree. We agree on this point but the West must help us to provide a propitious climate. But all these bombings, this support given to rebel groups, all that is counter-productive."

Air Strikes

Libyan television said the "colonial and crusader aggressors" hit military and civilian sites in Al Jufrah district in central Libya on Monday.

Rebels in the coastal city of Misrata, under siege for six weeks, scorned reports that Gadhafi had accepted a ceasefire, saying they were fighting house-to-house battles with his forces, who fired rockets into the city.

Western leaders also rejected any deal that did not include Gadhafi's removal, and NATO refused to suspend its bombing of his forces unless there was a credible ceasefire.

NATO Secretary-General Anders Fogh Rasmussen told a Brussels news briefing that Gadhafi's government had announced ceasefires in the past, but "they did not keep their promises".

"Any future proposal that does not include this, we cannot accept," he said, accusing Gadhafi of bombing, shelling and shooting civilians.

A resident of Misrata told Reuters there was heavy fighting on the eastern approaches and in the centre.

Rebels told Reuters that Gadhafi's forces had intensified the assault, for the first time firing truck-mounted, Russian-made Grad rockets into the city, where conditions for civilians are said to be desperate.

Human Rights Watch accused Gadhafi's forces of indiscriminate attacks on civilians in Misrata which violated international law. It said about 250 people had died.

At the front outside the eastern rebel-held town of Ajdabiyah, rebels buried the charred bodies of Gadhafi troops killed in air strikes and said they were advancing westwards.