Met chief Blair refuses to resign

He expressed his "deep regret" for the "tragedy" of the innocent Brazilian Jean Charles de Menezes's death.

But he insisted it was an "isolated breach" under "extraordinary circumstances" and gave his backing for all officers involved in counter-terrorism.

Sir Ian said he would now consider whether of the Met's operational procedures needed to be altered in the light of the verdict.

Speaking outside the Old Bailey, he told reporters: "As the judge noted, the failures alleged were not sustained or repeated.

"This case thus provides no evidence at all of systematic failure by the Metropolitan Police.

"And I therefore intend to continue to lead the Met in its increasingly successful efforts to reduce crime and deter and disrupt terrorist activities in London and elsewhere in the United Kingdom."

The Liberal Democrats called for the resignation of Sir Ian after his force was found guilty of breaching health and safety laws over the shooting of innocent Brazilian Jean Charles de Menezes.

Home affairs spokesman Nick Clegg said: "This guilty verdict makes it unavoidable that Ian Blair should take responsibility on behalf of his whole organisation and resign."

But Home Secretary Jacqui Smith said Sir Ian had her "full confidence".