Britney Spears will reportedly perform at Sunday's MTV Video Music Awards alongside former rival Christina Aguilera.

The pop pair, who first found fame as Mouseketeers on popular US children's show 'The Mickey Mouse Club' in the early nineties, are rumoured to be opening the 25th anniversary event together.

Although their joint appearance is said to be strictly under wraps, 26-year-old Britney has confirmed that she will appear on stage, despite her dismal performance at last year’s VMAs.

She said: "MTV has played an important role in my career. How can I not be there to kick off their 25th VMAs?"

A source added of her onstage antics at the 2007 ceremony, which included bad lip-syncing and a sluggish dance routine: "That shambles severely damaged the Spears brand. This time she’s determined it will be different."

Britney has been nominated for three gongs — Best Female Video, Best Pop Video and Video of the Year — all for hit track 'Piece Of Me'.