A black and white picture of John F Kennedy and Marilyn Monroe together, taken on May 19, 1962 during a Democratic fund raising event where Monroe sang "Happy Birthday, Mr President" for JFK, will be up for auction.

It was Monroe's last major public appearance before she died mysteriously in August 1962. After that, allegations of an affair with JFK surfaced.

The photograph was taken by White House photographer Cecil Stoughton. The revealing, rhinestone studded dress that she wore when she sang at the Madison Square Garden in New York, the one in the photo, was sold in an auction back in 1999 for £860,000.

Also in the picture was President Kennedy who seemed to be turning away from the camera while his brother Robert looked on.

"There is no other known photo of Bobby [Kennedy] with Marilyn or JFK with Marilyn, and it's not because they were never photographed together," according to filmmaker Keya Morgan, who is selling the picture.

"In fact, they were photographed together many times, but the Secret Service and the FBI confiscated every single photograph."

Mr Stoughton apparently told Mr Morgan that the photo survived because it was in the photographic dryer when the agents came to seize it.

Mr Morgan also said that it was not made available for the public eye because Mr Stoughton was in good terms with Jackie Kennedy, the president's wife, and did not want to upset her.

He purchased the photograph for his documentary on Ms Monroe. It is expected to reach £16,000 at the auction.

"You know, Marilyn died within months. President Kennedy died the next year and Bobby a few years from that. So what a haunting photograph, and it's the only one of any of them together," Mr Morgan said.