Cheryl and Rihanna plan duet

Singers said to be working on new project together

Cheryl and Rihanna have both apparently made space in their diaries to get together in the studio to record a new single together.

"They first spoke about a collaboration at the Brits and it's all still planned," a source told The Sun.

"They both want to do it. It's not a case of if, it's more when."

As well as exciting music plans, Cheryl is starring in new movie What To Expect When You're Expecting alongside Jennifer Lopez and new friend Cameron Diaz, who she wished a happy birthday via Twitter yesterday.