Their war of words started when Kelly said that Lady Gaga has the worst fans when it comes to cyber bullying, saying that despite her 65-pound weight loss, they have called her fat and told her to kill herself.
Lady Gaga responded in an open letter to Kelly, which she posted on her website LittleMonsters.com. In the letter, Gaga said that Kelly criticizes people all the time on her E! show Fashion Police.
In January, Sharon Osbourne delivered the counterstrike for team Osbourne, writing Gaga an open letter on her Facebook page saying Gaga is hypocritical and looking for publicity.
Then, things went quiet for a couple of months...
In the July issue of Cosmopolitan magazine, however, cover girl Kelly finally fires back at Lady Gaga herself, saying, "I loved Lady Gaga. I totally believed in everything she stood for, until I realized she's a great big hypocrite."
She went on to say that Gaga is "feeding on the freaks and geeks" to further her career and questioned whether or not she truly cares about the gay community.
Yikes! Those are some pretty harsh words for the "Born This Way" singer!
Lady Gaga is yet to respond to Kelly's latest comments, but we have a feeling she isn't going to take that one lying down.