The "big push" for Baghdad would begin "within 48 hours" with an intensive artillery bombardment supported by close air cover before the main body of troops stepped forward, said The Times.

The assault is likely to start to the southwest of Baghdad with an initial strike to breach Iraq's elite Medina division's lines north of Karbala and head on to the capital, it said.

"Intensive air strikes on the front lines of Republican Guard units had approximately halved their capability, setting the stage for a frontal ground attack within 48 hours," said The Financial Times.

Reports of the major ground offensive appeared in several other British newspapers with some quoting senior military officials saying the action would begin within hours.

The reports also came as a a senior US defense official in Washington said US troops had fought Iraq's elite Republican Guard south of Baghdad for the first time in the 12-day old war.

WAR.WIRE