After the bloodiest fighting of the three-week-old conflict between Libyan rebels and forces loyal to Muammar Qaddafi, the United Nations has demanded urgent access to scores of injured and dying in the western city of Misrata.
Libyan rebels ceded ground to Colonel Qaddafi's advancing forces today as the United States came under increasing pressure to arm the opposition and the UN appointed a humanitarian envoy.
World oil prices rose again, while the head of Nato, Anders Fogh Rasmussen said attacks on civilians by Qaddafi's troops could amount to crimes against humanity.
The rebels began pulling back from the key oil port of Ras Lanuf as fighter jets targeted defences on the edge of town, throwing up palls of smoke amid fears that government forces were gearing for an attack.
A doctor in Misrata said 21 people, including a child, had been killed in shelling and clashes there on Sunday, and 91 people wounded.
"The overwhelming majority of them are civilians, including a boy aged two and a half," he said of the casualties in Libya's third city, which had been shelled by tanks belonging to Colonel Qaddafi's forces.
At a news conference at Nato headquarters, Mr Rasmussen said: "These widespread and systematic attacks against the civilian population may amount to crimes against humanity,".
He said the "outrageous" response of Colonel Qaddafi's regime to protests had created "a human crisis on our doorstep which concerns us all" and reiterated his strongest condemnation.
"I can't imagine the international community and the UN standing idly by if Colonel Qaddafi and his regime continue to attack his own people systematically," Mr Rasmussen said.
The UN secretary general, Ban Ki-moon, named the former Jordanian foreign minister Abdul Ilah Khatib as his special envoy to deal with the regime on the humanitarian front.
Mr Ban's office said he noted that "civilians are bearing the brunt of the violence, and calls for an immediate halt to the government's disproportionate use of force and indiscriminate attacks on civilian targets".
Mr Khatib, 56, will leave for New York "in the next few days before travelling to Libya, where he should meet with all parties involved in the conflict," an associate of the former minister told AFP in Amman.
The UN called today for US$160 million (Dh588m) to cover relief support including shelter, food and sanitation for refugees as well as others who remain trapped in the country.
With the military situation worsening and population centres threatened, influential US politicians argued strongly for Washington to arm the rebels and secure a no-fly zone over Libya to thwart Colonel Qaddafi's air force.
The New York Times reported that US defence planners are preparing a range of land, sea and air military options in Libya in case Washington and its allies decide to intervene, including air-drops of weapons to rebels.
France meanwhile announced that a no-fly zone had won support from the Arab League, after talks between the League secretary general, Amr Mussa, and the French foreign minister, Alain Juppe, in Cairo.
Colonel Qaddafi has not hesitated to use his air power against rebel positions, and reports that his jets bombed protesters in Benghazi in the early days of the revolt are among alleged atrocities being investigated by war crimes prosecutors from the International Criminal Court.
The odd crackle of gunfire sounded early Monday across the eerily deserted streets of Ras Lanuf after vehicles loaded with armed rebels were seen speeding out of the town.
The rebels had been forced to withdraw from Bin Jawad, 30 kilometres west along the coast from Ras Lanuf, where at least 12 people were killed and more than 50 wounded when pro-Qaddafi troops ambushed outgunned and inexperienced rebel forces, medics said.
Ras Lanuf's sole hospital was empty Monday after the wounded were moved to Ajdabiya, further east in rebel territory.
The remaining rebel presence appeared very thin, with only about a dozen fighters manning the main checkpoint into the town.
World oil prices shot higher today, striking two and a half year highs on the turmoil in the Middle East.
Colonel Qaddafi, in an interview aired today by France24 television, repeated his accusation that al Qa'eda was fomenting the revolt against his regime and railed against France.
When asked about Paris's backing for the national council, the embryonic provisional government formed by rebels in the second city of Benghazi, Colonel Qaddafi said: "It makes one laugh, this interference in internal affairs. And what if we interfered in the affairs of Corsica or Sardinia?"
Italy's foreign minister, Franco Frattini, said Rome has begun discreet talks with the rebel "national council" to help find a way out of the bloodshed.
"We have better contacts than others" in Libya, which is an ex-Italian colony, Mr Frattini told RAI 1 television.
Britain was forced to admit its own, secret, attempt to begin negotiations with the rebels had ended ignominiously after opposition forces arrested a diplomat and a protection squad inserted clandestinely by helicopter.
In Benghazi, a rebel spokesman said the British team that landed nearby had not made prior arrangements, and was sent away.
An embarrassing mix-up in the international effort to evacuate tens of thousands of refugees saw a French ship leave empty from the Tunisian port of Zarzis after US planes appeared to have taken their human cargo.
The hi-tech helicopter carrier Mistral arrived after steaming from Toulon with 28 doctors aboard. It was supposed to take 900 Egyptians to Alexandria, but found most of them had already been airlifted to Cairo by US planes on Sunday.