Lady Gaga takes aim at Katy Perry's new tour

Lady Gaga has taken a subtle dig at pop peer Katy Perry, suggesting aspects on her new Prismatic tour look eerily similar to her past live concepts.

Perry kicked off the Prismatic World Tour in Belfast, Northern Ireland on Wednesday night (07May14), and when the Born This Way hitmaker saw photos of Perry's new show on Thursday (08May14), she took to Twitter.com to take a slight jab at the Roar singer, writing, "It looks like green hair and mechanical horses are the thing now."

Gaga previously sported neon green hair for a shoot with controversial photographer Terry Richardson, and she made an unforgettable entrance at last year's (13) American Music Awards, riding a large, white, mechanical horse.

Perry has yet to respond to Gaga's jab.