"@ladygaga I acted like a child last night. Just not into publicity stunts call me & we will end this like adults I don't want 2 fight anymore," the purple-haired E! star tweeted on Oct. 28.
The A-Listers' latest feud started after Gaga visited the X Factor UK set and posed with Kelly's mother Sharon Osbourne holding a birthday cake for Kelly.
The pastry may have been sweet, but Osbourne didn't perceive it that way. The opinionated star took to Twitter to share her frustrations saying, "Not to be ungrateful but why would you send me a birthday cake via my MOTHER in a country half the would away? #JustSendItToME #LoveNotWar."
She also posted a picture of the cake with the caption, "#EatMySh-t #Hypocrisy," but the post as since been taken down.
This celebrity feud originated long before bakers got involved. In 2009 Osbourne called Gaga a "butterface," causing the iconic crooner's band of loyal fans to launch into a series of threats against the Brit.
Gaga later penned an open letter to the Fashion Police star, criticizing her career choice saying, "Your work on E! with the Fashion Police is rooted in criticism, judgment, and rating people's beauty against one another."
But it was Sharon Osbourne who criticized Gaga's note, saying the eccentric star was bullying her daughter.
Clearly Mama Osbourne and Gaga have made up. After the "Applause" singer performed on The X Factor UK, the red-headed judge tweeted, "Blown away by Lady Gaga's performance and graciousness."