IT is one of the most notorious nude scenes in screen history. To some it is an alluring expression of pagan sexuality, to others a laughably strange moment of body-doubling.

Now Britt Ekland has re-ignited the dispute surrounding the identity of cinema's most discussed derrière, as featured in the 1973 cult classic The Wicker Man, by claiming it was a Glasgow stripper who writhed against the wall of a Dumfries hotel room.

The Swedish actress said she had only agreed to appear topless as barmaid Willow. She said she did not rate her posterior very highly, claiming it resembles "a ski slope".

"I didn't want to show my bottom but I shot myself in the foot," Ekland said on BBC1's Friday Night With Jonathan Ross. "They put in the ugliest, biggest bottom in the world. Mine was much smaller and much nicer. I recently found out it was a stripper from Glasgow."

Despite Ekland's assertion, many movie buffs contend the provocative dance was performed by a woman called Jane Jackson, who lived in Castle Douglas at the time of filming. Adding to the confusion is the film's musical director Gary Carpenter, who "can categorically affirm" that the body double was Lorraine Peters, an actress who appears later in the film weeping on a gravestone.

But the film's director, Robin Hardy, told the Sunday Herald he did indeed go to Glasgow to find a stripper that vaguely resembled Ekland. "We had to find someone rather quickly," he said. "The girl we found in a club was promised back the next day to the place she was performing. To my distress I discovered she was still with the crew, having a good time, two weeks later."

Whoever the replacement was, 65-year-old Ekland said she was less than pleased with her mystery body double and wished she had felt confident enough to bare all.

Ekland confirmed that she was pregnant during the shoot with son Nicholai, but denied long-standing rumours that this was the real reason she refused to strip, claiming she did not know she was pregnant at the time.

Hardy yesterday disclosed further details of the long-awaited follow-up to The Wicker Man, Cowboys For Christ. Joan Collins, who introduced Ekland to her former lover Rod Stewart, has joined Christopher Lee in the cast, replacing Vanessa Redgrave in the role of Lady Delia Morrison.

Although the new film is not a conventional sequel, there are more than passing similarities to the The Wicker Man. The film is about a gospel singer and her cowboy friend, both virgins, who set off from Texas to enlighten Scottish heathens about the ways of Christ. They are welcomed on the estate of a genial laird, again played by Lee, whose intentions turn out to be less than honourable.

A Celtic folk score has been composed by Keith Easdale along similar lines to the original soundtrack of The Wicker Man. Shooting is scheduled to begin on April 10 in some of the same Dumfries locations where the classic horror film was made.

Hardy revealed that scenes would be shot in Moniaive and at Kinmont House, as well as the City Chambers in Glasgow. "We're very pleased with the location and I'm very much looking forward to filming," he said.

The director, who wrote the novel Cowboys For Christ in 2006, added: "They thought they'd broken the mould after we made the original Wicker Man, but they were wrong." He described his follow-up movie as "another film with beautiful songs, sassy sex, a few good laughs and horror upon horrors ahead".

Christopher Lee said he was delighted to be reviving his partnership with Hardy. "The reason I want to work again with Robin is because he has written a book that is erotic, romantic, comic and horrific enough to loosen the bowels of a bronze statue," he said.

There will also be a third film in the line descending from The Wicker Man, which Hardy said would be a comedy.