Victoria Beckham to join the The Pussycat Dolls

Victoria Beckham is set to go back to her girl band roots -- by joining The Pussycat Dolls.

The former Spice Girl, 34, will join the group for one night only at Caesar's Palace in Las Vegas.

Pussycat Dolls spokesperson Alisa Boushey said: "Victoria's been in talks with the Dolls for some time and will be joining them on-stage.

"She would have done it sooner but it's been a question of her busy schedule. But it will be happening very soon."

Previous guest stars have included Christina Aguilera, Brittany Murphy, Charlize Theron, Eva Longoria Parker, Pamela Anderson and Paris Hilton.

Victoria will also design her own costume for the one-off performance. "This is a great opportunity for her," the insider tells Britain's Heat magazine.