While MTV swears that Britney Spears is not going to perform at the MTV Video Music Awards Sunday, a video of her rehearsing a steamy, new dance routine on a new song was leaked online fueling speculation of a surprise performance.

"I’m excited to open the entire show, to say hi to my fans and to be nominated," the 26-year-old singer said. "MTV has long played an important role in my career," she added. "How can I not be there to kick off their 25th VMAs?"

Although she isn't scheduled to perform but to do the opening for the event, the troubled pop singer was spotted back in the dance studio as she was practicing new moves to new music. The mid-tempo tune is reportedly called "Underground" and will be listed as Britney's first single for her upcoming not-yet-titled album.

Looking several pounds lighter, Britney is shown rehearsing with a group of dancers, and moving way smoother than last year's routine when she made a disastrous "comeback" lip-synching her single "Gimme More" while moving uncoordinatedly across the stage.

Though she is nominated for Best Female Video, Best Pop Video and Video of the Year for "Piece of Me," she has been nominated 17 times before but never walked away with a "Moonman."

Hosted by British comedian Russell Brand, with whom Britney taped some promotional ads, the 25th annual VMAs will air live on Sunday at 9 p.m. ET/PT from Paramount Studios in Hollywood.