The wait is over - Britney Spears and Iggy Azalea have officially released their new single 'Pretty Girls'. 

Azalea previously described the hook-up as a "classic, girly song" that fans will want to play as they are getting ready to go out.

Since the song's release, both Azalea and Spears have shared their excitement for their new track on Twitter.

Spears thanked her fans for their "amazing" feedback and teased more surprises to follow, while Azalea was full of admiration for her duet partner.

The duo will perform the track live at the Billboard Music Awards on May 17, marking Spears's first major awards show performance since her appearance at the 2007 MTV Video Music Awards.

The catchy pop track was originally written by Little Mix before the group decided it didn't fit their new sound.