US Defense Secretary Robert Gates arrived in Baghdad yesterday to tell Iraq's leaders the United States wanted faster progress in reconciliation efforts, a day after bombs killed nearly 200 people in the city.

"The Iraqis have to know... this isn't an open-ended commitment," Gates said, referring to Washington's troop presence in Iraq and level of support for the Iraqi government.

"Frankly I would like to see faster progress," Gates told reporters before departing Tel Aviv for Baghdad.

Suspected Sunni Al-Qaida militants detonated a string of bombs in mostly Shi'ite areas of Baghdad on Wednesday in the worst day of violence since a US-backed security crackdown was launched in February to stop Iraq sliding into civil war.

Gates later flew to the insurgent stronghold of Falluja, where he was due to meet US troops stationed there.

The visit is Gates' third to Iraq since taking over as defence secretary but his first since President George W. Bush's decision to send an extra 30,000 troops mostly to Baghdad.

Sectarian tensions between majority Shi'ites and once-dominant Sunni Arabs remain high since the bombing of a Shi'ite shrine in Samarra in February 2006 unleashed a wave of violence that has killed tens of thousands.

Washington, which has 146,000 troops in Iraq, says military progress should be matched with political reconciliation between Iraq's warring communities.

Hours before Gates landed, a suicide car bomber killed up to 10 people in southern Baghdad when he rammed his vehicle into a fuel truck, police said. Another police source said three were killed.

War-weary Iraqis yesterday vented their anger at the Baghdad security plan, which has cut death squad killings but failed to stop car bombings and other large-scale attacks.

Source: China Daily/Agencies