R&B superstar Mariah Carey has joined forces with R. Kelly for a new duet.

The Fantasy hitmaker took to her Twitter.com page on Thursday (27Sep12) to tell fans she and Kelly have met up in a recording studio in Chicago, Illinois to collaborate.

She showed off a photo of the two stars sharing a microphone, alongside the caption, "Me and Kells in the lab in Chi town (Chicago) working on a new song! Omg (oh my God) - his voice sounds A++"

Carey also tweeted her love for the I Believe I Can Fly hitmaker's hip-hop series Trapped in the Closet, branding it a "total classic".