Katy Perry debuts new song with giant disco ball in Auckland

Hear a snippet of Katy Perry's new track above!

Katy Perry has unveiled her new song using a giant disco ball installed in Auckland's Britomart precinct.

The site is one of 22 places around the world fans can have a sneaky listen to Perry's new song, which will be officially released on Friday.

Eager fans need to take their own headphones to the Nike store in Britomart and plug them into the disco ball to hear the song.

The premiere only lasts until the disco ball's battery runs out.

The new song is part of a relaunch for Perry, who has dyed her hair blonde and gone for a pastel pink look.