Britney Spears has asked Madonna to guest star on her upcoming world tour.

Britney is planning to unveil her superstar pal as a surprise guest when the pop tart kicks off her circus-themed comeback tour next year.

Britney joined Madonna onstage in Los Angeles last month during the U.S. leg of her Sticky & Sweet Tour in November, now Britney wants Madonna to return the favor when she kicks off her first tour in nearly two years in New Orleans in March.

“I’m choreographing and set-designing her show.There’s been talk of Madonna making an appearance, and there’s so many places we could take that. At this point the main issue is timing,” Britney’s choreographer Wade Robson reveals.