Ghadafi's defenders are putting up a fierce fight in the former dictator's hometown of Sirte.
Loyalists have forced revolutionary troops out of Bani Walid, a mountain city about 90 miles from Tripoli.
Sirte and Bani Walid are the main bastions of backers of the old regime in Libya's coastal plain, but smaller holdouts remain in the deserts of the center of the country - and another major stronghold, Sabha, lies in the deep south.
Revolutionary commanders say pro-Ghadafi forces have agreed to surrender most of the region about 50 miles east of Sirte.
Meanwhile, a military spokesman for the transitional government said revolutionaries do not know Gadhafi's location.
The Associated Press contributed to this story.