Rebel forces in Libya have clashed with forces loyal to Colonel Gaddafi about 80km south-west of the capital, Tripoli.
A rebel spokesperson in the Nafusa mountains said there had been heavy fighting on the outskirts of the strategic town of Bir al-Ghanam.
The rebels told the BBC they were making a push for Tripoli.
The spokesperson for the National Transitional Council, Guma el-Gamaty, told the AP news agency that Bir al-Ghanam - the focus of the latest fighting - was important as it was just 30km south of Zawiya, a western gateway to Tripoli.
Opposition fighters seized Zawiya in March before government troops drove the rebels out of the oil-refinery city. Fighting again broke out there this month.
Meanwhile, African leaders say Colonel Gaddafi has agreed to stay out of talks aimed at ending the conflict.
In a communique after talks on Sunday in South Africa, the African Union panel on Libya said it welcomed "Col Gaddafi's acceptance of not being part of the negotiations process". The statement did not elaborate.
The rebels control the east of the country as well as pockets of western Libya, including the Nafusa mountains.