Tripoli/Washington: Hammered by Gaddafi's tanks, heavy guns and rockets, rebel forces were in panicky retreat in east Libya on Wednesday, fleeing from the oil towns of Ras Lanuf and Brega.

Having halted the rebels march 100 kms from their leaders hometown of Sirte, Gaddafi's armoured columns chased the rebels right into Ras Lanuf, 370 kms west of the opposition stronghold of Benghazi, a daily reported.

Faced by a heavy barrage of shells exploding all round them, the rebel fighters fled on board pickup trucks reversing in advance triggered by heavy strikes carried out by French and British fighters on March 19.

The US President said though the "noose" was tightening around Gaddafi, but they were still not signs that he was seeking to negotiating an exit from Libya.

"Our expectation is that as we continue to apply steady pressure, not only militarily but through other means, Gaddafi will step down," Obama said.

A daily reported that the rout of rebels illustrating how much they rely on international power policy. "Only a day earlier, they had been marching westward; cocky they would take Sirte Gaddafi's main bastion in Central Libya. They reached 100 kms of the city before they were hammered by Gaddafi's forces, which pushed them back to Bin Jawad," Al Arabia correspondent said from the frontline.

But now Gaddafi's artillery is shelling even the key town of Brega.

As heavy battles raged on the eastern front, allied bombers and Tomahawk missiles kept up their pounding of the capital Tripoli.