Libyan rebels were today fortifying the town of Ajdabiya against a possible assault by Muammar Gaddafi's advancing forces.

A rebel spokesman said "intermittent" fighting between the two sides was taking place on a 50-mile stretch of road between Ajdabiya and the oil port of Brega.

Control of Brega has been split between the rebels and regime forces after days of fierce clashes.

Recapturing Ajdabiya would give Gaddafi's forces a significant boost as they continue to reverse the string of rebels' military successes when they began a march from the opposition-held east of the country to the capital Tripoli.