This one is written by Dodi Fayed's butler, Rene Delorm, and the marketing department is going for a two-pronged attack - a launch in Britain on July 1 to coincide with the princess's birthday followed by publication in the US on August 31 to commemorate her death.

"Extremely polite and always smiling" - Rene Delorm talks about Diana

But Rene Delorm insists he is not using his insider view of events last summer to make millions.

Had it not been for press speculation about his boss's alleged drug-taking and playboy lifestyle, Mr Delorm says he would never even have considered writing a book.

Mr Delorm's book: Romantic memoirs

"I loved my boss, I felt very upset by the two losses and on top of that to hear the calumny...." he said.

Mention money and innocent charm turns to anger and indignation.

"I get 8% and from that I have to pay my agent, my personal agent, my lawyer and the co-writers. I give half of what's left - what's left - to Diana and Dodi charities."

'I wanted to set the record straight'

Mr Delorm says that, encouraged by his son Bruno, he decided to "set the record straight", to assure doubters that Diana and Dodi were both truly in love, that the princess was not just another fling. In the very first chapter, he describes how his boss confided in him his plans to propose marriage to the Princess of Wales.

Princess Diana: Romantic holiday

Conscious of his faltering grasp of the English language ("I may not be the brightest, but I'm not the dumbest either"), Mr Delorm hired a lawyer and auditioned several ghost writers.

The book reads like a sentimental potboiler. But Mr Delorm says he is satisfied that the authors captured his emotional reaction - recorded over several months on tape - to what was "a love story that was real".

Intimate details

Dodi Fayed first met Mr Delorm eight years ago at the fashionable Spago restaurant in Los Angeles and was suitably impressed by his professionalism as head waiter. He hired him as a manservant.

Dodi: "True love for Diana"

They built up a close relationship - but like any butler worth his salt, he says he was careful never to speak out of turn or give advice where it was not wanted.

Last August, he flew to the south of France and joined the crew of the Fayed's luxury yacht in the Mediterranean where he attended to Dodi and Diana's every wish and whim.

Earl Spencer: Ridicules claims of a marriage proposal

So how would his boss feel about his manservant revealing intimate details of what he saw that summer, precise details of what they ate, what they wore, how they touched each other?

"How would they feel to hear what the media are saying about them?" he replies. "Finally someone is coming out as the only witness that can tell really what happened. They'd love me for that!"

In a BBC TV interview recently, Diana's brother dismissed claims that his sister and Dodi were to marry as "ridiculous". Mr al-Fayed hit back via the Daily Mirror newspaper saying the comments were "unwise".

Mohammed al-Fayed: 'Do what you have to'

Mr Delorm's book has already been serialised in the Sunday Mirror, but Dodi's manservant is at pains to point out that although Mr al-Fayed offered to retain him as staff, he turned him down wishing to stay in the US near his family.

Mr Delorm admits that Mr al-Fayed, was "surprised" when he told him about plans to publish his story, but he accepted the butler's motives, saying: "You do what you have to do."