Rihanna rejected Sia and Adele song

Rihanna rejected a song written by Sia and Adele.

The 'FourFiveSeconds' singer, 27, is currently working on her eighth studio album but declined a track co-written by the superstars despite their incredible writing credentials.

Sia, 39, - who has already released 'Alive' which she also penned with Adele - said: "We wrote three songs in two days and none of them made the cut and this was one of them.

"I said to [Adele], 'Do you mind if I pitch it to, say, Rihanna?' And she said, 'Yeah, but can you take my vocal off it because I don't want my vocal floating around out there on a demo.

"So I went and re-cut the vocal and everybody in my life was like, 'You can't give this away to anybody'."

Despite others insisting she kept the track for herself, she offered it to Rihanna for her new album 'Anti' but doesn't think it was "edgy" enough for her.

She told Ryan Seacrest: "Well actually I believe she did [get a chance to consider it] and she passed.

"We sent it to her, but it's not really her so I don't know why I thought that. It is a smash, but she's a little more edgy."

The track - titled 'Bird Set Free' - will now appear on Sia's seventh album 'This is Acting' due to be released in January.