Miley Cyrus is hitting back at Katy Perry’s claim that her tongue is gross. After sharing a kiss, the two pop stars are lashing out at each other, with Miley coming up with an equally tacky retort to Katy’s dig.

In February, pictures of Katy and Miley kissing on the lips made the rounds online. Katy was in the audience at Miley’s Bangerz Tour stop at the Staples Centre in Los Angeles when Miley singled her out and planted a kiss on her lips.

It was a brief kiss, which was supposed to be just a friendly smack, according to Katy. However, Miley went deeper and inserted her tongue inside her lips, which prompted Katy to push away immediately.

Katy told the Australian breakfast show “Sunrise” on Wednesday that she was surprised by Miley’s forwardness, insinuating that she found Miley’s infamous tongue gross.

“But then she tried to move her head and go deeper and I pulled away,” she told presenters Samantha Armytage and David Koch.

“God knows where that tongue has been!”

Never one to stay quiet, Miley retaliated with a couple of tweets, even involving Katy’s ex-boyfriend in the melee.

“Girl if ur worried abt where tongues have been good thing ur ex boo is ur EX BOO cause we ALL know where THAT been,” she tweeted.

She didn’t name the “ex boo,” but it’s likely that she was referring to John Mayer, whom Katy dated from August 2012 until February 2014.

“Dontchyouuuu act like you didn’t lurvvvvv it @katyperry,” Miley included an art of their infamous kiss.

Katy didn’t seem to mind Miley’s jibe.

She responded on Twitter:

“Oooo gurrrl I’m gonna give you the BIGGEST spanking when I see you in the UK bb!”