The elite forces began the attack with heavy shelling at about 3.30 pm (1230 GMT) as they edged ever closer to Iraq's second city, the news agency said.

Marines from 3 Commando Brigade were now pushing ever deeper into the city, with support from 59 Independent Commando Squadron, Royal Engineers, it said.

Artillery support, which could be heard across the suburbs, was being provided by AS90 self-propelled guns and 150 light guns of 29 Commando.

There were also huge Challenger 2 tanks from 2 Royal Tank Regiment, PA said.

A spokesman for the British defence ministry in London was unable to confirm the report.

Earlier on Sunday British tanks rolled into the outskirts of Basra, stepping up the pressure on Iraqi forces holding out in the southern port city, British military officials said.

British spokesmen said their forces were intent on seizing more territory as a show of force to residents and militias in Basra, which has been encircled by British and US troops for about two weeks.

SPACE.WIRE