The son of Libyan leader Muammar Gaddafi has gone on state television to proclaim that his father remained in charge with the army's backing and would "fight until the last man, the last woman, the last bullet".
Saif al-Islam Gaddafi's comments came after anti-government unrest spread to the capital Tripoli and protesters seized military bases and weapons.
In the regime's first comments on the six days of demonstrations, the younger Gaddafi warned the protesters on Sunday night that they risked igniting a civil war in which Libya's oil wealth "will be burned".
His rambling and sometimes confused speech, lasting nearly 40 minutes, followed a fierce crackdown by security forces who fired on thousands of demonstrators and funeral marchers in the eastern city of Benghazi in a bloody cycle of violence that killed 60 people on Sunday alone, according to a doctor in one city hospital.
Since the six days of unrest began, more than 200 people have been killed, according to medical officials, human rights groups and exiled dissidents. Lybia's response has been the harshest of any Arab country wracked by the protests that toppled long-serving leaders in neighbouring Tunisia and Egypt. But Gaddafi said his father would prevail.
"We are not Tunisia and Egypt," he said. "Muammar Gaddafi, our leader, is leading the battle in Tripoli, and we are with him. The armed forces are with him. Tens of thousands are heading here to be with him. We will fight until the last man, the last woman, the last bullet," he added.
Saif Gaddafi, who is the regime's face of reform, admitted that the army made some mistakes during the protests because the troops were not trained to deal with demonstrators, but he insisted that the number of dead had been exaggerated, giving a death toll of 84.
Western countries have expressed concern at the rising violence against demonstrators in Libya. Britain's Foreign Secretary William Hague said he spoke to Gaddafi's son by phone and told him that the country must embark on "dialogue and implement reforms".
In the speech, Saif Gaddafi offered to put forward reforms within days that he described as a "historic national initiative" and said the regime was willing to remove some restrictions and begin discussions for a constitution. He offered to change a number of laws, including those covering the media and the penal code.
Protesters had seized some military bases, tanks and other weapons, he said, blaming Islamists, the media, thugs, drunks and drug abusers and foreigners - including Egyptians and Tunisians. He also admitted that the unrest had spread to Tripoli, with people firing in central Green Square before fleeing.