Lord Snowdon, the husband of the late princess, will sell 50 prints of the photographs Tuesday at the Chris Beetles gallery in Mayfair -- including the nude photo he initially had not planned to offer -- the Times of London reported.
The sale of the nude photo has reportedly increased the rift between the society photographer and his son, Lord Linley, which has been strained since Linley auctioned several of the princess' former possessions without contacting his father.
"I'll bet this is Snowdon, as it were, cocking a snook at Linley," said Margaret biographer Christopher Warwick.
The paper said the photo represents the playful side that Princess Margaret showed around the time of her divorce from Snowdon in 1978, years before becoming a notorious stickler for royal protocol.
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