A previously unheard One Direction demo has leaked online.

As reported by The Sun newspaper's Bizarre column, the track called 'Half The World Away' has surfaced and is said to have been penned by Harry Styles - but didn't make the cut for their 2012 LP 'Take Me Home'.

However, the version that is making its way around the web only features Harry's vocals.

He sings: ''If you were a good friend you'd always be there when I need it, 'cause I'm on my knees and babe I'm bleeding. And it kills me that you're not around.''

The chorus goes: '''Cause there's a time, there's a place and I'm always gonna hear your name. There's a right, there's a wrong, and now I see that all along, I messed up, you'll be fine. I'm going to sleep alone tonight.''

The lyrics then take a turn for the worse and it's been suggested that's why the track never saw the light of day.

On another line, Harry sings: ''I started drinking, I don't know half of what I'm thinking. I'm deep in, I'm scared I'll stop breathing. We've started to lose who we are.''

One Direction fans haven't heard anything new from the chart-toppers - who formed on 'The X Factor' - since their 2015 album 'Made In The A.M.'.

Last month, Harry, Niall Horan, Liam Payne and Louis Tomlinson celebrated their 10th anniversary with the launch of a website and new content such as music videos and behind-the-scenes footage.

However, fans who were hoping for a reunion and new music were out of luck.

Niall explained why they didn't plan new releases to mark the milestone.

The 26-year-old singer said: ''We've barely spoken about it. The band got together in July 2010.

''It's the 10-year anniversary coming up - we were chatting if there was anything we could release. We came to the conclusion there was nothing.''

The 'What Makes You Beautiful' group - which also featured Zayn Malik, until his departure in March 2015 - have been on a hiatus since 2016 and each member has subsequently pursued their own solo careers.