SHE was one of the world’s most iconic sex symbols starring in hit movies including Gentlemen Prefer Blondes and The Seven Year Itch.

Now a Spanish collector is selling a film he claims is a young Marilyn Monroe having sexual intercourse while she was still unknown.

The grainy, six-and-a-half minute film is to be auctioned in Argentina by Mikel Barsa, who is hoping to raise around 350,000 euros from the sale.

He claims the black-and-white footage was shot before 1947, when the aspiring actress was under 21 and still known as Norma Jean Baker.

Barsa insists the 8mm film is an exact copy of a 16mm reel found more than a decade ago which was bought by a collector for 835,000 euros.

However, some experts have denied that the woman in the film is Monroe, claiming that many of her characteristics including her chin, lips and teeth are not the same.

But Barsa – who will auction the film at a collectors’ fair in Buenos Aires on August 7 – insists it is Monroe.

“This film shows the real Marilyn Monroe – it was only later that the studios discovered her and transformed her,” he said.