Britney Spears is thought to have asked her ex Justin Timberlake to perform on her US tour.
According to Now Magazine the singer wants Pharrell Williams, 35 and Madonna, 50, to make appearances too.
The 27-year-old is also said to have asked Sir Elton John, 61, to join her on stage.
Spears is planning to stay in London for four months ahead of her gigs at The O2 arena in June.
A source told the News of the World: "It will be amazing. Britney can’t wait to move to London. She thinks she’ll have more freedom."
Spears, whose new album Circus is out now, is rumoured to be announcing more dates this week.
