Libyan interim government forces have launched what they are calling the “final assault” on the loyalist stronghold of Sirte, while pledging to appoint a new transitional government soon after the strategic coastal city is captured.

National Transitional Council fighters seized new territory in and around Sirte on Monday, including the nearby small town of Qasr Abu Hadi – where Moammar Gadhafi was reported born in a nomad tent in 1942.

A Red Cross convoy delivered oxygen and other urgently needed medical supplies to the Ibn Sina hospital in Sirte after an earlier attempt was aborted due to heavy fighting. Fleeing medics said patients were dying on the operating table at the facility because there was no oxygen and no fuel for the hospital's generators. Four anti-Gadhafi fighters were killed in Monday's clashes and 39 others wounded.

In Tripoli, Libya's transitional leaders vowed to step down after Sirte is secured and the country's liberation declared. Interim Prime Minister Mahmoud Jibril said he has requested that the declaration be announced after Sirte is captured because that would ensure all of Libya's sea, land and air entry ports are secure.

He acknowledged that fighting will continue in a number of pockets deep in the southern desert, including Bani Walid. But he said it is important to declare victory and begin rebuilding the country.

Jibril and NTC head Mustafa Abdel Jalil already had pledged to take no further part in the country's future government, as required by the country's interim constitution. The pledge was intended to reassure the public they will not suffer under another dictatorship.

NTC leaders also announced a minor Cabinet reshuffle Monday, with Jibril retaining his position and taking on the job of foreign minister. A new minister for Libyans killed and wounded also was named.

Meanwhile, the International Organization for Migration says it has begun evacuating more than 1,200 African migrants from the southern town of Sabha, one of Mr. Gadhafi's longtime strongholds.

The IOM said Monday the migrants left on a convoy of 15 trucks that is expected take about a week to reach the border of Chad and Niger. From there, they will travel to the northern Chadian city of Faya Largeau before being taken to their final destination inside Chad or elsewhere in Africa.

About half of the migrants are from Chad, with the rest from 10 other African nations. The IOM said fighting had prevented them from getting aid into the town, which provisional authority forces gained control of late last month.