The 'Neon Lights' hitmaker and 'Happy' singer will join hip-hop duo Macklemore & Ryan Lewis, rapper A$AP Rocky and American duo Twenty One Pilots, as performers at the event at Los Angeles' Microsoft Theater on Sunday (30.08.15).
Following the announcement, Demi, 23, took to Twitter to share her excitement about the upcoming performance of her new single 'Cool For The Summer'.
She wrote: ''I'M PLAYING THE #VMAs B*****s!!!!!!!! #CoolForTheSummerVMA @MTV (sic).''
Pharrell also expressed his eagerness to perform, saying he ''can't wait'' to take to the MTV stage.
He tweeted: ''Can't wait to perform at the #VMAs this year! See you Sunday at 9/8C on @MTV (sic).''
They will join the previously announced 'Can't Feel My Face' hitmaker The Weeknd, with more performers and presenters set to be announced shortly.
Miley Cyrus will host the star-studded ceremony this weekend, which will see Kanye West receive the prestigious Video Vanguard Award, which has previously been won by Britney Spears, Justin Timberlake, Michael Jackson and U2.
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