Miley performs 'Rebel Yell' with Billy Idol

We knew that Miley Cyrus was a rebel, but now it's official.

The singer joined '80s rock legend Billy Idol onstage at the iHeartRadio Music Festival in Las Vegas to belt out the title track from the rocker's 1983 hit album.

The singer emerged onstage towards the tail end of Billly's mini-set - which kicked off with back-to-back mega-hits 'Dancing With Myself' and 'White Wedding'.

Miley could hardly contain her excitement, enthusiastically jumping around and hollering, "with Billy f---ing Idol".

RELATED: Miley Cyrus and Liam Hemsworth have reportedly got hitched!
RELATED: Miley Cyrus and Liam Hemsworth sing a Justin Bieber duet

The iHeartRadio Music Festival also features performances from Drake, Sia and U2, before kicking off night two on Saturday (Sunday in Australian time) with Britney Spears, Sting and Ariana Grande.

Want more celebrity, entertainment and lifestyle news? Follow Be on Facebook,Twitter, Pinterest, Tumblr and Instagram