Lady Gaga is the highest new entry on Forbes magazine's annual list of the world's most powerful celebrities.

The US star debuted at number four, behind fellow singer Beyonce at number two and Avatar director James Cameron and number three.

Forbes described Lady Gaga's success as “a mixture of extreme theatricality, catchy hooks and an image that is edgy, yet business friendly”.

The annual list, which is based on earnings and media spotlight, was topped by TV show host Oprah Winfrey.

Other music stars inside the top-10 included Britney Spears at number six, U2 at number seven and Madonna at number ten.

From the film world, Twilight co-stars Robert Pattinson and Kristen Stewart were notable new entries at number 50 and 66 respectively.

(by Jason Gregory)