Bernard Hogan-Howe has vowed to put the fear into London's criminals as he was named Britain's top police officer.
The former Merseyside chief constable was selected to be the new Scotland Yard Commissioner after pledging to oversee a "new, more transparent era for the Met".
Flanked by the Home Secretary and London Mayor Boris Johnson at Scotland Yard, Mr Hogan-Howe said: "It's the highest accolade that any police officer could have."
Outlining his targets, he added: "The idea is to make the criminals fear the police and what they are doing now."
The Mayor said: "It was a very strong field but I think the Home Secretary and I were agreed that Bernard's performance was outstanding, and he really commended himself above all by his relentless focus on building on the work of Sir Paul Stephenson and Tim Godwin in driving down crime.
"The Home Secretary has alluded to what happened in Merseyside where crime came down by 40% in three years and I know it's that kind of approach that Londoners will want to see, and that Londoners will want to give their full support to achieving.
"And I'm sure that we at City Hall, everybody in the city, will wish Bernard very well indeed."
