Madonna, Robbie 'in X Factor talks'

Madonna, Robbie Williams, Lady GaGa and Rihanna are reportedly being lined up to appear on the upcoming series of The X Factor.

Beyoncé, who sang with eventual winner Alexandra Burke on last year's show, is also said to be in the frame to return to the ITV1 programme, The Sun reports.

A source said: "The last series proved anything is possible when Beyoncé performed with Alex. The final got 15 million viewers and that is enough to entice the biggest stars onto our stage.

"This year is going to be bigger than ever - we are planning to get the best names in music. Madonna and Robbie would be sensational."

Show host Dermot O'Leary previously revealed that Britain's Got Talent runner-up Susan Boyle would perform a duet on this year's X Factor.

It has been suggested that a reported £6 million increase in the budget of the show could be used to pay for the star appearances.