Stars, including Victoria Beckham and Christina Aguilera, and tennis pro Serena Williams have appeared nude for a book in aid of the Elton John AIDS Foundation.

The photos that will appear in a publication called "Four Inches" will see Posh Spice completely naked except for a piece of Cartier jewellery and a pair of Jimmy Choo shoes.

The other stars who will appear in the book include Kate Moss, Geri Halliwell, Paris Hilton, Serena Williams, Minnie Driver and Sarah Ferguson.

The pictures will also be seen in the April issue of society magazine Tatler, just before the book comes out in May.