The 27-year-old 'I Kissed A Girl' hitmaker, whose marriage to funnyman Russell Brand was officially dissolved, took to the microphone under the name Katherine.

Perry belted out Smith's classic hit 'Welcome To Miami' with a pal, and footage of the night shows the singer finishing the track and then calling out "I love my best friend".u00a0

Katy Perry. Pic/Santa Banta