One Direction star Harry Styles has reportedly written a track with John Legend.

According to The Mirror, the Story Of My Life singer is thought to have penned twenty new tunes, including a song with Legend.

The X Factor USA winners Alex and Sierra confirmed the news, with the tabloid quoting Sierra as saying: "Our favourite [song] is one that Harry Styles wrote with John Legend, it's beautiful and lovely.

“[Harry] is actually an amazing writer, he's pitched us a few other good ones and they're really good."

A source went on to add: “It’s a testament to Harry’s talents that he can work alongside John - who is, without doubt, one of the most gifted songwriters of a generation.”

The duo's mentor Simon Cowell previously praised their new music, writing on Twitter: "Am listening to the Alex and Sierra demos for their upcoming album. Fantastic. It's seriously good. I can't wait for everyone to hear it."

It is the first time a member of 1D has officially worked on material outside the group, with Styles said to be credited to 26 songs on the American Society of Composers, Authors and Publishers.

Over the weekend, One Direction were forced to deny rumours that they are splitting up, insisting they've just taken a break from work.