Embarrassment at the forced resignation of Boris Johnson’s deputy mayor was threatening to engulf the wider Conservative Party today as Labour sought to drag David Cameron into the furore.

Ray Lewis, who headed the mayor’s agenda on youth crime, resigned last night after an independent investigation was launched into fraud and sex allegations during a period when he was a Church of England priest.

He was forced to go when Mr Johnson yesterday decided he could no longer provide him with the “backing necessary to continue” having been misled over his role as a magistrate.

While the mayor said that Mr Lewis remained an “inspiring figure”, he said his confidence had been shaken by the discovery yesterday that his aide was not a “fully-fledged Justice of the Peace”.

In a statement, Mr Johnson said he accepted Mr Lewis’s resignation with “extreme reluctance”.

But he added: “I cannot deny, however, that my confidence in Ray was shaken by the discovery today that he is not a fully fledged Justice of the Peace and I cannot deny that to be misled on this issue has made it harder for me to give Ray the backing necessary to continue in his role as Deputy Mayor.”

Mr Lewis claimed on Thursday that he was a Justice of the Peace, but this was contradicted yesterday by the Government.

Mr Johnson said: “I still hope that he can clear his name. I cannot deny, however . . . that to be misled on this issue has made it harder for me to give Ray the backing necessary to continue in his role as deputy mayor”.

Mr Johnson had at first vowed to support his deputy, despite learning that Mr Lewis had been barred from holding office in the Church of England because of an alleged serious misdemeanour.

Mr Lewis said in a statement last night that the “drip, drip” of allegations was getting in the way of important work and he did not want anything to obstruct the Mayor of London’s task. He added that the announcement of an independent inquiry, which was to be headed by Martin Narey, a former director-general of the Prison Service, had done little to calm the avalanche of allegations.

But he also commented on the wider claims made against him, saying he was resigning in the face of an “avalanche” of allegations. The “drip, drip” of allegations was “getting in the way of the very important work of this Mayor and his vision for London,” the former deputy mayor said.

He added: “I cannot allow the things that I have been into, up to and around me to obscure the important business of this mayoral team.

Times Recommends

• Oh no, Mr Darling: you have failed
• BBC survives dogfight over Kennel Club expose
• Where the Rosetta belongs can’t be set in stone