Halle Berry appears as a Bond girl

"She is doing a song for the film but she won't be acting," Madonna's spokeswoman in London said.

It is not yet known if Madonna's song will be the title tune.

She joins a long line of famous names who have recorded songs for Bond films, including Paul McCartney, Tom Jones, Shirley Bassey, Tina Turner and Nancy Sinatra.

Work on Bond 20 began in January at Pinewood Studios near London.

Fifth time

Brosnan is making his fourth appearance as Bond, alongside co-star Halle Berry, the US star of Swordfish.

The Irish star has extended his contract to play James Bond for a fifth time.

The latest Bond episode will open with a dramatic hovercraft chase in the demilitarised zone between North and South Korea, with action moving to Hong Kong, Cuba, Iceland and London

Bond's nemesis will be a North Korean general played by Rick Yune, a former male model and martial arts expert.

The film marks the 40th anniversary of the popular series which began in 1962 with Dr No, starring Sean Connery.