Sir Cliff Richard has withdrawn from a charity concert at Canterbury Cathedral on September 26 because he did not "want the event to be overshadowed by the false allegation", his spokesman announced. The statement added: "He is sorry for any disappointment or inconvenience caused."

Cliff RichardCliff Richard denies the allegations [Getty/Andreas Rentz]

Police searched Sir Cliff's Sunningdale apartment last week as part of an investigation into an alleged sexual assault on a young boy in Sheffield in 1985. The pop star, who was in Portugal at the time, denies any wrongdoing.

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The singer's decision to pull out of the charity event comes after the 73-year-old hired the high profile lawyer Ian Burton - regularly considered one of the finest criminal lawyers in the business.

The investigation has already come under fire after it emerged that South Yorkshire Police tipped off a BBC reporter about the search. The director general of the corporation and head of the police force were told on Monday they would be called to give evidence to MPs over the handling of the investigation. The BBC's live coverage of police officers searching the premises has led to allegations of a witch hunt.

Cliff Richard homeCliff Richard's home in Sunningdale [Getty/Peter Macdiarmid]

Keith Vaz, the Commons home affairs committee chairman, said he was "concerned by the methods or process" that the BBC used in its live broadcast.

Sir Cliff's close friend Cilla Black said the allegation was "completely false," adding, "I, like everyone else, was very shocked to hear of these allegations and I am absolutely positive that they are without foundation."

The charity concert was part of series of events at Canterbury Cathedral to mark the church's 40th anniversary, reports the Guardian.