Iraqi and US forces were poised to strike a key Shia militia stronghold in southern Iraq yesterday as Nouri al-Maliki, the Prime Minister, pushed ahead with his campaign to rid the country of al-Mahdi Army gunmen.

Iraqi army tanks, armoured troop carriers and infantrymen surrounded al-Amarah, a lawless tribal city near the Iranian border that is renowned for its smuggling rings. It once held a British base but the army was mortared so heavily by al-Mahdi Army irregulars that it withdrew to patrol the Iranian frontier.

Mr al-Maliki has told the militiamen that they have until Thursday to surrender their weapons before the Iraq forces — backed by US troops and air power — move in. “The military is deployed to ensure total control of the city without leaving any gaps for the militants to flee,” General Nassir al-Abadi, a senior Defence Ministry official, said.

Mr al-Maliki, who gained a boost in popularity when his forces took Basra from murderous militias, is hoping to push forward with his campaign to isolate al-Mahdi Army, led by Hojatoleslam Moqtada al-Sadr, the Shia cleric who once ordered a full-scale revolt against the US occupation.

Colonel Mahdi al-Asadi, a spokesman for al-Amarah police force, said that the operation would target any illegal militia groups, not specifically al-Madhi Army. “It will target outlaws even if they are government officials. It will not target any militia specifically but those who are criminals,” Colonel al-Asadi said.

Hojatoleslam al-Sadr has announced a series of reforms since his street fighters lost control of Basra and he was forced to cut a deal allowing Iraqi government troops into his once-impregnable stronghold of Sadr City in Baghdad. Last week he said that his al-Mahdi Army would shift its focus to civilian action, with only a small armed wing being retained to fight the Americans.

The Iraqi Government is trying to manoeuvre the Sadrist movement into renouncing violence and transforming itself from one of the most-feared militia groups into a political organisation. It already runs charities and welfare groups among the poorest of the Shia population but retains the right to attack US forces.

The cleric has sent a delegation to al-Amarah ordering his militia fighters there — many of whom have already fled or buried their weapons — to respect a ceasefire he declared with Iraqi forces.

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