The "Roar" singer took to Twitter on Thursday to respond to Miley Cyrus' kiss diss, shortly after the "Bangerz" pop starlet made some questionable remarks about her friend's dating history with ex-beau John Mayer.
"Oooo gurrrl I'm gonna give you the BIGGEST spanking when I see you in the UK bb!" Perry wrote.
The brunette beauty's post was in response to Cyrus' tweets earlier in the day, shading Perry after she made a joke at Miley's expense during a recent TV appearance.
While doing an interview with an Australian morning show earlier this week, Katy was asked why she denied a makeout session with the 21-year-old at a recent concert.
"I just walked up to her to give her a friendly girly kiss," Perry explained. "She tried to move her head and go deeper and I pulled away. God knows where that tongue has been!"
Cyrus fought back, writing, "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 later added, "Dontchyouuuu act like you didn't lurvvvvv it."
Do you think this is this a real feud or friendly banter between pals? Sound off, and click "Launch Gallery" to see more celebrity feuds!