Katy Perry will perform 'Roar' live for the first time at the MTV Video Music Awards.

The 28-year-old singer - who hasn't performed at the VMAs since 2009 - will take to the stage at the Barclays Centre in Brooklyn on August 25 alongside Macklemore, Justin Timberlake, Miley Cyrus and pop pal Lady GaGa, who will also sing her new track 'Applause'.

The brunette beauty penned her pop anthem after a tumultuous year - during which she divorced comedian Russell Brand and embarked upon a rocky relationship with John Mayer - and she previously admitted the track was like musical therapy to her.

She said previously: ''It's a bit of a self-empowering type of song. I wrote it because I was sick of keeping all these feelings inside and now speaking up for myself, which cause a lot of resentment.

''Obviously I've been through a lot of therapy since my last record and that's what this is about.''

The song was released early after it leaked online on Saturday (10.08.13), while her chart rival Lady Gaga's new tune 'Applause' suffered a similar fate.

Following weeks of Gaga and Katy's fans battling it out on Twitter over whose comeback would be more successful, the eccentric singer decided to put an end to things.

Writing in a statement on her website, Gaga raged: ''I really want the second half of 2013 to mark a change in pop, when music is not mangled by trash talk and tabloids.

''I support pop music and more artists putting out new music just means more for music lovers to enjoy. Don't fight with Katy's fans, or anyone. STOP THE DRAMA. START THE MUSIC. (sic)''