Until Tuesday night, Blair had only suffered one defeat in parliament over planned legislation since coming to power in 1997 -- a controversial move to hold terrorist suspects for up to 90 days without charge.

But just over two months after that setback, the lower House of Commons twice voted against him on the Racial and Religious Hatred Bill, backing the unelected upper House of Lords which had already blocked aspects of the proposals.

In further embarrassment, it emerged that Blair did not take part in the second of two votes on amending the bill -- which the government then lost by just one vote due to a sizeable revolt amongst Labour backbenchers.

Northern Ireland Secretary Peter Hain admitted the government had been taken by surprise and said a period of reflection was needed, particularly to find a "better way forward" with "regular (Labour party) rebels" who opposed Blair.

Asked on BBC radio if the prime minister's no-show at the vote made it personally embarrassing, he replied: "Well, yes, maybe."

"But if you look at what we were trying to do, this is very controversial legislation. We are in a situation where Muslims don't have the protection that, for example, Jews and black citizens do and there remains an anomaly."

In the wake of the defeats, Home Secretary Charles Clarke announced that the government would bow to the Commons' will and send the bill for royal assent, minus its defeated amendments.

Blair has personally campaigned for tougher measures to confront global terrorism in the wake of the July 7 attacks in London which left 56 people dead, including four suicide bombers.