MET Commissioner Sir Ian Blair today defended his force's "shoot to kill" policy.

Sir Ian was forced to reiterate his backing of the policy at a meeting of the Metropolitan Police Authority.

At the meeting it was revealed that nearly 800 terror suspects have been reported to police since the July 21 failed suicide bomb attacks.

But most of those reported were innocent.

Concerns about Operation Kratos - the guidelines which say suspected suicide bombers can be shot in the head - were raised after the shooting of innocent Brazilian electrician Jean Charles de Menezes.

Sir Ian strongly denied that the guidelines were being extended to non-terrorist incidents and repeated his assertion that officers were not "trigger happy".

He told the MPA: "We are living under different terms of normality, with different rules. The circumstances of having terror suspects on the loose following the failed bombings had never happened before in the world and we were faced with new challenges."

Sir Ian insisted that the policy had always existed and that firearms officers were trained to kill suspects.

Sir Ian added: "Officers will be able to use their judgement as they have always been able to do.

"In the case for example of a ten year old girl who has been taken hostage with someone holding a knife to her throat, and its clear he is going to try and cut her head off, the officer would be justified in using a shoot to the head policy."

Britain's top policeman also denied that "shoot to kill" was more likely to be used against people from ethnic minority backgrounds. "Of the eight people shot dead only two came from ethnic minorities. I completely refute any accusations otherwise.

"We need some form of public debate which looks into the use of lethal force in a liberal democracy."

After the meeting Alex Pereira, a cousin of Jean Charles de Menezes, said: "There has been no public discussion or debate about a policy where it is shoot first and ask questions later'.

"This sort of policy does nothing to make the people of London feel safer or have more confidence in their police."

"He has not answered a single question about this policy who devised it, who authorised it and who should be held to be accountable for its failures."