Katy Perry's Twitter rant at Calvin Harris

Katy Perry's not a happy girl.

The Firework star has launched in a Twitter rant against Calvin Harris after the Scottish DJ pulled out of his support slot on her UK tour.

Harris was scheduled to support Katy in Dublin on Monday night (28.03) but it was left to Perry to tell fans it wasn't happening

She tweeted, "Fyi All Uk & Ireland Related Shows @CalvinHarris will Not be joining in on the fun and has Cancelled last minute."

But Calvin hit back, also on Twitter, saying he had good reason for backing out, "Sorry to all who wanted to see me with Katy - her team suddenly moved the goalposts, and i was to appear on stage with "no production".

"It would have looked s**t, sounded s**t - trust me you would have been more disappointed Seeing the show than u are with me cancelling. That's the honest truth. Her show is Awesome, you'll all have an amazing time without me. (especially w/o (without) me DJing on a cardboard box in front of a pink curtain)."

But Perry didn't buy it "Funny the goal post seems to be perfectly fine for New Young Pony Club, Yelle, Robyn, Marina & The Diamonds to name a few... Or how bout Janell Monae (sic) and her 16 piece band... Etc... it's fine, I'm used to you cancelling on me, it's become ur staple!"

Katy show moves to Nottingham on Wednesday (30.03) before gigs in Bournemouth, Cardiff, Newcastle, Birmingham, London and Liverpool.

Shawn Mendes Jingle Bell Ball 2016

Watch ALL The Live Performances From The Jingle Bell Ball 2016

Liam Payne & Cheryl Baby

Liam Payne's Sister Speaks Out After New Pics Appear To Confirm Cheryl Pregnancy Rumours

Leigh-Anne Pinnock joins Snapchat

80+ Of The Best Popstars You Should Have On Snapchat

My Capital App

Want To Control The Music On Capital? Now You Can With Our New App!