The State Department Thursday authorized the evacuation of all U.S. government personnel and dependents from Somalia and urged private U.S. citizens to leave "as soon as possible."

The State Department announcement said that once all U.S. Embassy personnel leave the country, "the embassy will not be able to offer any assistance to Americans. The Department of State advises all private U.S. citizens in Somalia to depart the country as soon as possible."On Wednesday, State Department spokesman Richard Boucher described the situation in Somalia as "confused" and said that the United States wants to evacuate the remaining Americans from the country, but there is no assurance that an air evacuation could be arranged safely with the fighting going on near the U.S. Embassy.

Boucher said there are 37 American diplomats left in the capital, plus fewer than 50 private American citizens.

Fighting broke out in the city Sunday as centrally based USC insurgents, with the backing of the northern Somali National Movement and southern-based Somali Patriotic Front, tried to overthrow the government.

On Thursday, rebels rejected President Mohamed Siad Barre's plea for a cease-fire and said they were preparing a final offensive.

Some foreigners were fleeing the country, but those involved in large-scale evacuation plans have said a halt in fighting must precede any attempt to bring the foreigners out.

"A cease-fire only for evacuation of foreigners has no meaning," Abdul Kadir, the foreign secretary of the insurgent United Somali Congress, told The Associated Press in Rome.

In a communique issued later in Rome, the United Somali Congress said 10,000 more rebel soldiers had arrived in Mogadishu, the capital, from the Somali hinterland to join in a battle against Siad Barre loyalists.

The president is believed holed up in an airport bunker.

About 40 foreigners managed to leave Somalia Thursday on a fishing boat from Brava, 50 miles south of the capital, according to a Canadian diplomat in Nairobi. They included an unknown number of Britons, Americans, Australians and other nationalities as well as 17 Canadians.