Boris tells Met: Blair case must not harm London

The Mayor's deputy has written to Sir Paul Stephenson, deputy commissioner of the Met police, demanding assurances at the highest level that the row over whether the embattled Sir Ian Blair should quit will not affect the day-to-day protection of the capital.

In the letter last week Kit Malthouse, who has responsibility for the Met, urged Sir Paul Stephenson - the favourite to take over at Scotland Yard if his boss goes - to confirm the police would "keep their eye on the ball" despite the storm.

Sir Ian is facing allegations of race bias against senior Asian officer Tarique Ghaffur, accusations of possible irregularities over awarding contracts to a friend and the Stockwell shooting inquest which begins later this month.

He came out fighting yesterday as it was revealed he faces being axed by Christmas if the inquest rules that Jean Charles de Menezes was unlawfully killed.

But the revelation that Mr Johnson is concerned the effectiveness of the Met could be at risk as a result of the controversies will ramp up the pressure on the Met chief to step down regardless.

A senior City Hall source told The Standard: "At the moment he [Sir Ian] has a lot of personal things on his plate in terms of de Menezes, Ghaffur and a whole range of issues which are taking his attention.

"Boris has actually been in touch with the Met as recently as last week to seek reassurances that this is not going to take people's eye off the ball.

"What we're concerned about is whether we are doing an effective job in protecting London."

Support for the Met chief among senior officers has drifted as the series of controversies has engulfed the Yard.