Justin bieber and Usher talk about relationship

Justin Bieber and Usher have spoken together about their relationship in a US magazine interview.

The pair, who have been friends for years while Usher was mentoring him to pop fame, talked to Billboard Magazine about 18-year-old Justin's changing sound and the bond he shares with his 33-year-old mentor.

JB said: "I don't want to lose my young fans, but I also want to mature and develop. I always keep one foot out of my comfort zone, trying new things and experimenting — if you don't, people will get bored.

"Seeing the smiles on people's faces and how I affect them when I perform makes me want to give them the absolute best experience they can possibly get."

To which R&B star Usher added: "I'm happy that Justin knows that without me even saying that. You really do want to make sure that you bring along fans that have always been there, but make sure that you grow and chart new territory."

Asked what advice he'd been given by his mentor, Justin said: "He takes me back to Michael Jackson, but also Fred Astaire and all these other people that I probably would've never looked up.

"And Usher's always told me, 'You need to work hard, but also play hard. Strive to be the best, but have fun doing it.'

"What's great is that in Usher, I have a mentor that's been doing it so long and has been successful in everything that he's done," Justin continued. "He's made some mistakes, too, but he's learned from them, so he can tell me what to do and what not to do."

Biebs has also found time to tease his followers on Twitter with the promise of more info about his forthcoming tour soon.

He said: "#BELIEVEtour announcements this month...stay tuned."