Justin Bieber has released his new song 'Lonely', and admitted it was "hard to listen to" at first because it brought back memories of "tough" chapters of his life.

The 'Never Say Never' hitmaker has collaborated with Benny Blanco on the new tune, and he took to Instagram to share a clip from the music video, which sees actor Jacob Tremblay playing a young Justin, who is standing all alone in a theatre during his early career.

Justin wrote: "Lonely is out now with @itsbennyblanco. When he and @finneas showed me this song to be honest it was hard to listen to considering how tough it was to get through some of these chapters. I went into the studio and sang through it which wasn’t easy but started to really see the importance of telling this story! It made me realize we all feel lonely at times! (sic)"

The 26-year-old star - who was discovered aged 13 - admitted it made him "emotional" to see Jacob play a young version of himself.

He added: "Being someone in my position I believe it is powerful to express vulnerability and that’s why I believe this song is so powerful! And @jacobtremblay is so talented. It was emotional to see him play me from the outside looking in (sic)"

Justin's latest release comes just a month after he and Chance the Rapper dropped their gospel-tinged collaboration 'Holy'.

He wrote at the time: "New era. New single. It's begins. #HOLY this Friday ft. @chancetherapper jbsoon.com (sic)"

The track was accompanied with a music video helmed by Colin Tilley, which features Wilmer Valderrama and Ryan Destiny, with the latter playing Bieber's love interest.