At least three US publishers are reportedly locked in a battle for the rights to the 38-year-old actress' autobiography, reported Daily star.
"Her book is guaranteed to top the bestseller lists in virtually every country on the planet and even an advance of that size would be recouped within weeks. Whoever gets her will be sitting on a gold mine," a source said.
The Oscar-winning actress always wanted to write a book about her life.
"She has always wanted to do this and believes the time is now right," the source said.