Rihanna has spoken out about why she recently collaborated with ex boyfriend Chris Brown.

Brown was convicted of assaulting the singer in 2009 so when news filtered out that the pair were due to collaborate, eyebrows were raised.

They teamed up on remix of Rihanna's 'Birthday Cake' and also a new version of Brown's 'Turn Up The Music'.

Speaking to Ryan Seacrest on his radio show, she said she approached Brown to feature on 'Birthday Cake' - because he was the only person who made "sense" to have on the recording. She said:

"I reached out to him about doing 'Birthday Cake' because that's the only person that really, it made sense to do the record. Just as a musician, despite everything else, that was going to be the person."

She continued: "You know, I thought about rappers, and I've done that so many times, and the hottest R&B artist out right now is Chris Brown. So I wanted him on the track, and then in turn he was like, 'Why don't you do the remix to my track?' and it was a trade off."

She also moved to defuse any potential split between the fans of the two artists. She added:

"We did two records. One for my fans. One for his fans. And that way our fans can come together. There shouldn't be a divide, you know? It's music, and it's innocent."