Oh! Oh! Yes, Minister!

Another political sex scandal breaks. Yet this time it's not John Prescott but a 'senior Tory' and his book of lurid confessions. Marie Woolf investigates

An explicit book telling of the athletic, complex and serial sexual shenanigans of a "senior Tory politician" is about to be published. It promises to be about as welcome to David Cameron's newmodel Conservatives as a cloudburst at a true-blue garden party.

And, with the author coyly hiding behind the by-line "Anonymous", all Westminster is now agog with speculation about his identity. In the words of one observer: "He's either got a very fertile imagination, or an awful lot of people are going to be wishing he kept the cap on his pen."

The memoir, provocatively entitled Unzipped, recounts encounters with prostitutes in hotel rooms, orgies, and flirtations with girls half his age. With echoes of Alan Clark's diaries, the author describes how he buys presents for his lovers in the House of Commons gift shop, identical "baby doll" basques for two in a lingerie shop near Parliament and visits to brothels at party conferences.

But the identity of the author is a closely-guarded secret and already the hunt is on at Westminster to unmask the serial Tory seducer, who reveals himself as a 46-year-old Tory councillor, former parliamentary candidate and political lobbyist.

The married politician, known simply as "Anonymous", recounts a string of sexual adventures, in explicit detail, including watching a male friend being buggered by a "lady-boy" prostitute.

The book is so lurid that the publisher, Virgin, has printed an "Adults Only" warning on its cover telling parents this political memoir is not suitable for aspirant teenage politicians.

Billed as "Scandalous sex secrets: the very private journal of a public servant", it describes its author meetings with MPs, lobbying to get motions put down in Parliament and tells how his hopes of becoming an MP were dashed by the 1997 Labour landslide.

He describes flirting with "a rather pretty" political researcher he is having lunch with in Portcullis House, the new parliamentary building, before heading off for a seedy encounter with a Czech prostitute in Harrow. "You would be forgiven for thinking it is fiction, but the events in this book are all true," said a spokeswoman for the publisher. "Unzipped is a fascinating insight into what really goes on among politicians, and inside the mind of a middle-aged man."

The author himself lays a few clues to his identity, saying he "is an insider, a very minor player among those who make the rules and uphold the value systems you have to live by. To meet me you, would correctly guess that I am in early middle age, but beyond that I bear remarkably few distinguishing features. I am neither fat nor thin, neither plain nor good-looking, neither ideologically left wing nor right".

He adds that his motivation to write the book was that "after a lifetime in politics I have fallen out of love with the establishment and broken free from the shackles of social convention."

Last week, there was talk at Westminster that the author had not done enough to cover his tracks. So recent are some of his social encounters, which begin in 2002, that some political figures believe they remember them. They believe the author may also have stood for the European Parliament and is a "wet" Conservative with pro-European links.

The whispers are that his vivid description of his attempt to seduce a young beautiful political Labour hack whom he admits is "someone young enough to be my daughter" contained enough details to out him. Thinly-disguised references to New Labour haunts have already been identified. A party he describes at the Cosmopolitan Club, is believed to be the Commonwealth Club, a central London restaurant popular with Labour ministers.

While his description of how his quarry changed political allegiances from Labour to the Tories has already got tongues wagging among Labour hacks who believe they know who she is - not least because he includes the giveaway detail that her parents, who are divorced, both live on the same street.

When The Independent on Sunday put the name of a senior political lobbyist, former Tory candidate and councillor to the publisher yesterday it refused to confirm or deny his identify.

"We are not saying whether it is or isn't him," said a spokeswoman.

But, colleagues of this figure, well-known in political circles, have for some reason recently been made to sign gagging clauses preventing them from talking to the press.

The memoir, a page-turning romp which leaves so little to the imagination it could be a bonkbuster novel, could prove highly damaging if the identity of the author is revealed, not least because of the "kiss and tell" nature of many of his revelations could also reveal the identity of other figures he describes, having affairs and liaisons with prostitutes.

The father of two describes how at a political dinner his wife told him she would give him her blessing to having sex with other women. Perhaps she did not realise how enthusiastically he would fulfill her wishes.

Extract: 'In love, and she's young enough to be my daughter'

"On our 20th wedding anniversary and at the age of 46, I fall ridiculously, hopelessly, head-over-heels in love with someone young enough to be my daughter: 'Angela'.

It is the birthday of Paul, 'New Labour' and therefore a political opponent, but also a friend. Together with a fellow Conservative, John, I join him and his party in a very trendy wine bar that's all late 20th-century Scandinavian minimalism amid Victorian splendour. On one of the sofas sits Angela... Do I believe in love at first sight? The answer has to be 'yes' though I do think it's conceptually more complicated than that. The initial reaction has to be reinforced by interaction to turn into love. Nonetheless, the attraction is instant and massive. When she stands, I can scarcely take my eyes off her; she has the figure of a model topped by the fine, even features of an English rose, framed by long chestnut hair."

Taken from 'Unzipped', by Anonymous, published by Virgin Books at £12.99