Ahmad al-Shibani stressed that any peace move initiated by the interim government - which he branded as a proxy agent of the US occupation of Iraq - would be welcomed by al-Sadr.

"We want to stop the bloodshed, maintain the honour and integrity of the Iraqi people, and bring this crisis to an end," he told Aljazeera.

His comments came a few hours after the Iraqi Ministry of Interior stated that US occupation forces supported by Iraqi national guardsmen would ''soon'' begin a large-scale offensive on Najaf.

In further signs that an attack on Najaf was imminent, Iraqi police forces in the city forced journalists to immediately leave the area. Najaf sources told Aljazeera some journalists refused to leave and were hiding in the besieged city.

While US forces have stressed that they will respect the sanctity of the holy shrine of Imam Ali, Aljazeera is reporting that a single shell breached the outer sanctum of the shrine, hitting an outer wall and killing one al-Mahdi army fighter.