The most prominent figure in a US-backed revolt of Sunni sheikhs against al-Qaida in Iraq was killed today by a bomb planted near his home in Anbar province, 10 days after he met with US President George Bush, Iraqi and US officials said.

US President George Bush is set to ask the US for more time to let success bloom in Iraq even as the assassination of a Sunni sheikh who revolted against al-Qaida sent a chilling reminder of the pervasive instability there.

The most prominent figure in a revolt of Sunni sheikhs against al Qaida in Iraq was killed today in an explosion near his home in Anbar province, Iraqi police and tribal leaders said.