01/04/2013 09:27 am ET Updated Dec 06, 2017

Princess Diana Rare Photo With Mystery Man To Be Auctioned Off (VIDEO, UPDATED)

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A never-before-seen photo of a young Princess Diana lounging with a mystery man -- cryptically marked NOT TO BE PUBLISHED -- is expected to fetch a hefty sum at an upcoming auction.

The extremely rare picture was discovered among the Daily Mirror's photo archive. It's inscribed with the date 26 February 1981 (believed to be the day it was bought) on the back. Notice anything interesting? That's two days after Diana and Prince Charles's engagement was officially announced by Buckingham Palace.

According to the Daily Mail, the photo was likely taken on a Swiss ski vacation around 1979 or 1980, when the young future princess would have been 18 or 19. The young man, they speculate, may be Diana's former boyfriend Rory Scott, or close friend James Colthurst. On the ledge next to the couple is a bottle of Johnnie Walker whiskey, and the words "NOT TO BE PUBLISHED" are scrawled across it.

Eric Caren, who bought the Mirror's photo library seven years ago and is the pic's owner, told The Daily Mail: "It's an intimate photo - I don't know the man in the picture and he could be a friend or a boyfriend.

The photo is presumed to be worth around $1000, but experts tell the AFP it's expected to sell for much more.

UPDATE: The identity of the mystery man was confirmed to be Adam Russell, an Old Etonian and the great-grandson of former Prime Minister Stanley Baldwin. According to Andrew Morton, the royal biographer, “They kept each other company while the others went skiing and at the end of the holiday Adam was somewhat smitten but absolutely nothing happened." Very interesting.

princess diana photo

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