London — The Duchess was forced to apologise for a “serious lapse of judgment” after being filmed trying to sell access to her husband, the Duke of York, for £500,000.

She told an undercover reporter posing as a businessman: “I can open any door for you.”

It was not the first time that the Duchess has faced acute embarrassment when her private moments were caught on camera.In 1992 she was photographed topless with John Bryan, her Texan financial adviser, apparently sucking her toe.

Nine years ago the Countess of Wessex fell victim to a sting by a News of the World reporter known as the “fake sheikh”.

Believing him to be a wealthy Arab businessman who wanted to hire her public relations firm R-JH she made a series of indiscreet remarks about politicians and other public figures, unaware that she was being recorded.

Most damagingly, she suggested that her royal status could enhance her clients’ businesses.

She was heard to say: “Most of our clients do end up having extra mentions in the press or, you know, additional profile.

“The chances are you’ll get people interested: ‘Oh gosh, they’ve employed the Countess of Wessex’s PR company’.”

Last year Prince Harry was forced to apologise after a home video emerged in which he called a fellow army officer a “Paki”.

In the clip, filmed during his Sandhurst training, the Prince introduced fellow officer cadets waiting around at RAF Brize Norton in Oxfordshire to catch a flight to Cyprus.

Homing in on Ahmed Raza Khan, a member of his platoon who is now an officer in the Pakistani army, he introduced him as “our little Paki friend”.

Five years ago a photo opportunity on the ski slopes of Switzerland turned into a PR disaster for the Prince of Wales when comments not meant for public consumption were picked up by a television microphone.

Asked a question about his forthcoming marriage to the Duchess of Cornwall by the BBC’s Royal Correspondent Nicholas Witchell he was muttering to his sons: “I can’t bear that man.

“I mean, he is so awful, he really is.”