FOR years it was the object of salacious speculation by disreputable tabloids, but the private life of Charles and Diana, the Prince and Princess of Wales, has resurfaced unexpectedly in a very different literary form. A respected American novelist is about to publish a book of short stories imagining the sexual encounters of famous couples.

Robert Olen Butler, who won the Pulitzer prize for fiction in 1993, portrays the heir to the British throne as a distracted husband “humphing in confusion” as he makes love to a wife who is “gaunt from her virginity”.

In a short but cruel and morally dubious account of a supposed love-making session at the Majorcan palace of King Juan Carlos of Spain, Butler fantasises the thoughts of both Charles and Diana as they engage in a starkly passionless episode.

While the prince is said to find his wife “chlorine and ammonia and antiseptic”, Diana’s thoughts seemingly drift to childhood memories as a way of escaping what appears to be an ordeal. Charles compares his bride with his then mistress, Camilla Parker Bowles: “I would cling to a horse who’s been ridden.”

Butler, 61, denied last week that he was either courting cheap controversy or invading the privacy of the prince or any of the other living characters in his book, Intercourse, which is due to be published in America in May. Other couples he examines include Bill and Hillary Clinton and George and Laura Bush.

“The book is not really about the fitting together of the bodies,” said Butler, who is professor of creative writing at Florida State University. “It is a rendering of the inner consciences of these people, a way into the inner selves of the characters.”

Butler has long been acclaimed for his skills as a literary ventriloquist, inserting himself into the heads of characters in his stories, often at moments in extremis. He won his Pulitzer with A Good Scent from a Strange Mountain, a series of stories narrated by different Vietnamese immigrants.

Two years ago he published Severance, short stories imagining the final thoughts of decapitated heads, based on scientific evidence that the brain keeps functioning for up to 60 seconds after the head has been severed from the body. His characters included Marie Antoinette, John the Baptist, a victim of Al-Qaeda and a dragon slain by St George.

“I’ve always agreed with W B Yeats, who said that sex and death are the only things that can interest a serious mind,” Butler said in an interview at the 19th-century former plantation house where he lives outside Tallahassee. “Severance was my death book; Intercourse is my sex book.”

Butler is far from the first author to try to imagine Diana’s thoughts; he is not even the first in his own family. His fourth wife, Elizabeth Dewberry, wrote a 2006 novel called His Lovely Wife, in which Diana’s supposed thoughts feature prominently.

Dewberry was also responsible for Butler’s other claim to literary fame, as the author of a recklessly candid e-mail describing the subsequent breakdown of his marriage. The e-mail duly popped up on the internet, temporarily transforming Butler from literary titan into heavily blogged cuckold.

The experience may have coloured his attitude to other people’s sex lives, for he abandons all restraint in diving into the bedrooms of couples as diverse as Adam and Eve; Bonnie and Clyde; Attila the Hun and his 12th wife; King Henry VIII and Anne Boleyn; and even Santa Claus and a female elf.

Butler’s past work has impressed critics with its wit and literary flair. In Intercourse he imagines a couple on board the Titanic at a crucial moment: “I feel her tremble at my touch and as if by magic the whole room trembles with her.”

Yet the book seems likely to be criticised for its invasion of the privacy of its living subjects. Butler depicts the Clintons as law students having sex for the first time while each is thinking of their future political careers. “Before she’s done here I’ve got to figure out how to get on top,” muses Bill.

Butler’s new work was welcomed by John Carey, a reviewer for The Sunday Times: “It’s something that’s gone on in literature for a long time: think of Shakespeare’s Antony and Cleopatra, a great world class love story, and Shakespeare imagines how it was. I’m not really surprised someone should do this.”

Hugo Swire, a former shadow culture secretary, attacked the work as part of the growing Diana industry. “You’re never going to stop people exploiting other people’s misfortune. I just hope nobody buys it,” he said.

Butler likened his work to a quote by Carlos Fuentes, the Mexican writer, who once described the novel as “a pack of lies hounding the truth”.

Additional reporting: Holly Groom

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