Libyan rebels clinging on against pro-Gaddafi forces have lashed out at the West for not coming to their aid.
Troops loyal to Colonel Muammar Gaddafi have been relentlessly bombarding the key eastern city of Ajdabiyah for the past two days, raining rockets and artillery and tank shells on the area and sending most of its population fleeing.
The city, with a population of 140,000, is the gateway to the rebel-held eastern half of Libya.
If Gaddafi troops take the city, the rebel stronghold of Benghazi would likely be their next target.
"People are fed up. They are waiting impatiently for an international move," said a rebel spokesman in the city of Misratah, the last rebel-held city in western Libya, which came under heavy shelling on Wednesday.
"Gaddafi is exploiting delays by the international community. People are very angry that no action is being taken against Gaddafi's weaponry."
At the United Nations in New York, supporters of the international effort to impose a no-fly zone over Libya were set to push for a Security Council vote on a draft resolution aimed at preventing air attacks by Gaddafi's forces against his people.
But Russia, China, Germany and others have expressed doubts.
The US, however, is now pushing for even broader action to protect civilians.
US Ambassador to the UN Susan Rice said: "The US view is that we need to be prepared to contemplate steps that include, but perhaps go beyond, a no-fly zone.
"We are discussing very seriously and leading efforts in the Council around a range of actions that we believe could be effective in protecting civilians."
UN secretary-general Ban Ki-moon urged all sides to accept an immediate ceasefire.
He warned Col Gaddafi's forces against a march on Benghazi, saying a campaign to bombard such an urban centre would place civilian lives at risk.
But Col Gaddafi says he does not expect rebels to put up a fight in Benghazi.
Asked whether he expected a battle in the country's second city, the dictator said: "No, no I don't think so."
He told Lebanon's LBC television: "All the places where they (rebels) are fortified, are now being sterilised with the help of the people... who say where their locations are."
The International Red Crosshas withdrawn from Benghazi ahead of a possible attack, but said plans to return once security has improved.
One of Col Gaddafi's sons, Saif, claimed on Wednesday that Benghazi will fall to government forces within 48 hours whether or not there was a no-fly zone.
The army had issued an ultimatum to residents in the city, which has now expired, warning them to leave rebel-held locations and weapons storage areas.
A broadcast on Libyan TV addressed the city's people, saying the army was coming "to support you and to cleanse your city from armed gangs".