Princess Michael of Kent, at a book-signing luncheon thrown at the Randolph Hotel yesterday, told guests not to expect any tales from the last 50 years in her book about Royal mistresses.

She was launching her book, Cupid and the King, about five kings' mistresses from different walks of life and social classes.

Richard Ingrams, editor of the Oldie magazine, hosted the event, which was sponsored by cruise company Swan Hellenic. He said: "One of the things the Royal family do not generally do is write books.

"I think Queen Victoria was the last one to do it, but her books were not exactly bestsellers."

Other authors at the booksigning were Edward Enfield, launching Freewheeling Through Ireland, and Christopher Matthew, with his new book, Summoned by Balls.

Retired TV presenter Sir Ludovic Kennedy and Inspector Morse creator Colin Dexter were also there.