A married royal said to have performed a gay sex act on his senior aide on a kitchen floor as a Stringfellows stripper egged him on also took drugs, a jury heard yesterday.

Ian Strachan made the claim about the unnamed royal that he is accused of blackmailing while “pitching” a story to a tabloid journalist, the Old Bailey was told.

James Weatherup, a News of the World reporter, said that he was first approached by Mr Strachan last year about recordings he had made of the aide — described in court as a balding, camp predatory homosexual who “minced” in a manner more akin to the Mr Humphries character John Inman played in the 1970s TV show Are You Being Served?

Mr Strachan and Sean McGuigan, 41, had secretly recorded eight hours of video and audio of the aide, named as Witness D, snorting cocaine and making disparaging comments about the royal, named as Witness A, and other members of the Royal Household.

Commenting on a meeting with Mr Strachan at the socialite’s Chelsea home in March last year, Mr Weatherup said: “As the story developed we became more interested in A because Ian had said that A took drugs.

“It’s in the tapes. There is an allegation of taking drugs. We’d be interested in proving that A took drugs. We knew that D took drugs because it was on the tape.”

Ronald Thwaites QC, for Mr McGuigan, described the aide as a “habitual liar” and a “boastful braggart” because of his claims on the tapes.

Cross-examining Mr Weatherup, the barrister asked whether the aide appeared “a middle-aged man, balding, with a paunch, a little past his prime” and who could hardly be considered “irresistible”.

Mr Weatherup replied: “I thought he was quite entertaining. I thought he was full of joie de vivre, quite ready to gossip on a regular basis about people in the Royal Family.”

Mr Thwaites: “"You describe him as flamboyant. Did he have affected mannerisms that some people would consider to be camp?”

Mr Weatherup: “Yes, I think that’s fair.”

Mr Thwaites: “Was it on the scale of John Inman, would that be fair, in Are You Being Served? Was that how he was cavorting himself around?”

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