The BBC defended Graham Norton after he made a joke about the Duchess of Cornwall's looks - in front of Prince Charles.

In the latest bad-taste episode for the corporation, the flamboyant presenter implied Camilla was "not hot" at a rehearsal for the Royal Variety Performance.

Below the belt: Graham Norton

His quip followed a raunchy performance by the Pussycat Dolls.

Norton said: "And there you have the Pussycat Dolls singing to the prince, 'Don't cha wish your girlfriend was hot like me?"

The gag had Britain's Got Talent winner George Sampson, 15, in hysterics - but it is not known how Prince Charles reacted.

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Last night the BBC said the joke was being included in the recording of the show, which Camilla also attended.

A spokeswoman said it was "light banter" and "no offence" was meant to Camilla. The Royal Variety Performance, held at the London Palladium last night, will be shown on BBC1 next Wednesday.

The corporation has been rocked by recent controversies. Radio 1 DJ Chris Moyles was in hot water after implying Polish women were only good for ironing and being prostitutes, while Jonathan Ross and Russell Brand are still dealing with the fal lout f rom obscene prank calls to actor Andrew Sachs. Norton himself is no stranger to controversy, in 2003 he had to apologise after making a joke on his Channel 4 show about the death of Bee Gee Maurice Gibb.