The US military announced on Friday the deaths of six more soldiers in Iraq, hours after US President George W Bush predicted a bloody summer lay ahead.

Five of the soldiers died on Thursday while another was killed on Tuesday by a roadside bomb in Tikrit, 175 km north of Baghdad, the military said.

April was the worst month this year for the US military since the invasion to topple Saddam Hussein in 2003, with 104 soldiers killed. About 90 have been killed in May so far.

The total death toll for US troops since the invasion now stands at 3,440.

The US military has deployed thousands of extra troops around Baghdad and other areas in a last-ditch attempt to drag Iraq back from the brink of all-out sectarian civil war between majority Shi'ites and Sunni Arabs dominant under Saddam.

The crackdown is an attempt to buy time for Iraqi Prime Minister Nuri al-Maliki's government to meet political benchmarks set by Washington, including a revenue-sharing oil law, aimed at promoting national reconciliation.

Bush told a news conference in Washington on Thursday he expected heavy fighting in Iraq in the weeks and months ahead.

He predicted insurgents and Sunni Islamist al-Qaida would try to influence the US debate on the war by launching major attacks before General David Petraeus, the commander of US forces in Iraq, hands him a progress report in September.

"It could be a bloody - it could be a very difficult August," Bush told reporters.

One of the fiercest critics of the US presence in Iraq, influential Shi'ite cleric Moqtada al-Sadr, made his first public appearance since the crackdown began when he attended Friday prayers in the holy city of Kufa.

The US military has said he went into hiding in Iran to escape the crackdown. Aides to the young cleric, who led two uprisings against US forces in 2004, say he never left Kufa.

Sadr's sudden reappearance comes at a crucial time for Iraqi politics. Six Sadrist ministers withdrew from Maliki's weak and divided government last month in protest at the premier's refusal to set a timetable for a US troop withdrawal.

Meanwhile. a joint British and Iraqi force killed Friday the leader of Shiite cleric Moqtada al-Sadr's Mahdi Army militia in the southern Iraqi city of Basra, British military and official of Sadr office said.

"An Iraqi special force backed by British killed in the afternoon Wisam al-Waili, also known as Abu Qadir, leader of MahdiArmy in Basra along with three of his aides while he was driving his car in a commercial street in central Basra," an official from local Sadr office said on condition of anonymity.

The attack sparked tensions in the city, some 550 km south of the capital, as hundreds of Mahdi militiamen spread on the main streets and intersections in the city, the official of the Shiite movement of Sadr, which runs the Mahdi Army, told Xinhua by telephone.

The British military confirmed the incident, saying that a militia leader was killed by Iraqi forces in a "precision strike" on his car in central Basra.

(Xinhua News Agency, China Daily via agencies May 26, 2007)