Selena Gomez praises Justin Bieber's comeback

Pop star Selena Gomez has applauded her ex-boyfriend Justin Bieber for making a successful career comeback.

The two singers dated on and off for three years, but split for good in 2013.

Justin endured a number of personal problems while they were together and after the break-up, including several brushes with the law.

Selena admits critics thought she was "stupid" for dating the troubled star, but insists his pop revival has shown the world the Justin she fell for.

"While people were writing that I was stupid for being in it, this is what I always saw in him. I'm like, duh!" she tells the New York Times.

Justin has scored a huge hit with his comeback single, What Do You Mean?, which is rumoured to be about Selena.

The song landed him number ones in both the U.S. and U.K. and precedes his upcoming fourth studio album.

The currently untitled record is set for release in November (15), setting up a chart battle with One Direction, who will also be releasing a new album in the same week.

Justin also recently opened up about his romantic woes, admitting he is still healing following his split from Selena.

"I went through a period of trying to figure some stuff out," he told Australian radio's The Kyle & Jackie O show. "I haven't been in a relationship for a while... I'm chilling, hanging out by myself... I'm a relationship type of guy. I love being in love, and I love cuddling, I love all that stuff but I got my heart broken so I'm just trying to let that heal up..."