Brian McFadden believes that Justin Bieber needs to take a break - or his career might crumble.

The Irish singer left Westlife in 2004 and he told Entertainmentwise that it was partly due to exhaustion.

He believes that because whilst One Direction have five members and can share the workload somewhat, Bieber needs to take some time off from music to recharge. McFadden said:

"I think with One Direction and Justin Bieber, the difference is there's five of them boys so, one of them might have a bad day but the rest of the four can keep it going. But Justin just seems to be constantly going, working so hard, so someone's going to have to tell him to take a break soon. That's what happened to me. If I'd been able to take a break before Westlife, I probably would have still been in Westlife."

He continued: "You have to be in control of it and take the time off and enjoy it because you don't want to get to the stage where you're not enjoying it anymore. This is the best job in the world, but as long as you appreciate what you're doing."

The former Westlife man isn't the first person to warn Justin Bieber over his hectic schedule - Robbie Williams recently told the Canadian to watch out for the dangers of burning out and dabbling in drugs.