September Song JP Cooper Download 'September Song' on iTunes
Rihanna says she wants a duet with Katy Perry.
Showbiz Spy reports she said: 'We want to hopefully make something.
'We are talking about it right now, but it's hard because we are both so busy. It will be something fun. Something out of the box.'
The two are friends, with Rihanna throwing Katy a bridal shower last year.