Madonna wants Cate Blanchett to star in her new musical.

A source told Britain's The Sun newspaper: "The final script is now written and the locations have been scouted. Madonna is now trying to assemble the cast and put the finances in place.

"The first scene of the film is an old woman in her 90s living on her own in a Parisian flat. She starts to tell her life story to her housekeeper. It turns out the old woman is Wallis Simpson.

"There will be a song for each decade of her life."

Madonna - whose last acting role in a movie was in 2002 flop 'Swept Away' - had been planning to start work on the film last year, but it was put on hold while she finalised her divorce from Guy Ritchie.

A source said at the time: "Madonna sees Wallis Simpson as her next big film project. She is fascinated by this American commoner who refused to conform or offer explanations for her tangled love life.

"It was all systems go until the divorce, when everything was put on the back-burner."

Edward was forbidden from marrying Wallis because she was divorced. In 1936, he gave up the throne so he could be with her. The pair married and moved to France, where they lived out their lives as the Duke and Duchess of Windsor.

Edward's brother, George VI, replaced him as king.