Boris Johnson has launched an inquiry into allegations of financial and sexual misconduct by his deputy mayor, Ray Lewis, after it emerged that Mr Lewis is a clergyman who has been disciplined and barred from office by the Church of England.

Mr Lewis today denied the claims as "complete rubbish" and "an attempt to smear me". However, the Church's Chelmsford diocese, where Mr Lewis had ministered as a vicar, issued a strong statement in which it pledged full cooperation with the Mayor's office in any investigation, confirming that a "misdemeanour" had taken place.

A church spokesman said: "Between 1999 and 2005 Ray was placed under the formal disciplinary structures of the Church of England, and his ministry was restricted.

"This was because a misdemeanour of such seriousness had been committed that in the opinion of the Archbishop, the person concerned should not exercise his ministry for the time being."

The claims relate to an incident involving a parishioner at Mr Lewis's former church in East London, who said she had been a victim of Mr Lewis, but was "no longer a victim". Mary Massey, aged 71, told The Times she had given the clergyman about £29,000 after she retired as a college lecturer. She called in police when he went abroad and she was unable to trace him, and even used a private investigator.

However, she said that Mr Lewis had since repaid all the money with interest and she held no grudge against him. She said she had trusted him because of his position as a man of the cloth, but she had not wanted the matter dragged up again.

She said Mr Lewis had offered a good rate of return for her money. "He has a lot of qualities and is very charismatic," she said. "I do not normally flash my money around but a lot of pressure was put on me in the nicest possible way."

Mr Johnson announced the independent inquiry into what were described as sexual and financial allegations - which Mr Lewis categorically denies - during a press conference at City Hall.

Mr Lewis denied that he was suspended while serving as an Anglican priest, but said he left of his own volition. "I would say to you that the allegations are without grounds," Mr Lewis said. "I would say that the allegations are malicious."

He added: "Those that know me well know that I’m not a saint. I’m also not the person painted by these allegations. I have never harassed anyone, I have never defrauded anyone."

He added that he was happy to face questions on any of the claims. "Working in Boris’s administration has been the greatest honour of my life. I will not allow the office or Boris’s trust in me to be tainted in any way."

He described the allegations as "totally unfounded and complete rubbish". Asked if he thought someone had a vendetta against him, the deputy mayor said: "Clearly so."

Mr Lewis, who is deputy mayor for young people, was ordained in the Church of England in 1990, and served in the Parish of St Matthew, West Ham in the Diocese of Chelmsford between 1993 and 1997. He then moved to Grenada in the Diocese of the Windward Islands, where he ministered until 1999, after which he resigned from ministry all together.

This is the second major blow to Mr Johnson’s administration since he was elected London Mayor on May 1.

Last month, one of his senior advisers quit after apparently remarking that Caribbean immigrants should go home if they did not like London. Mr Johnson insisted that James McGrath, his political adviser, was not a racist. But the Mayor said it would only provide "ammunition" to his critics if Mr McGrath was to remain in post.

Mr Johnson accepted the resignation of Mr McGrath, a 34-year-old Australian, after an interview with the adviser appeared on the internet on June 22.

In it, he was challenged with the suggestion by prominent black commentator Darcus Howe that Mr Johnson’s election could cause an exodus of Caribbean immigrants to their homelands.

In response, Mr McGrath was quoted as saying: "Well, let them go if they don’t like it here."

The Mayor said Mr McGrath had been quoted "out of context" by Marc Wadsworth, a so-called citizen journalist, but the remarks made it "impossible" for him to continue in his role.

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