Lady Gaga, Kelly Osbourne Twitter beef intensifies: fashionista celebrates 29th birthday, tells ARTPOP songstress 'eat my sh*t' after b-day cake peace offering

Lady Gaga and Kelly Osbourne are NOT the greatest of friends. But when the "Fashion Police" beauty celebrated her 29th birthday on October 27, the ARTPOP songstress tried extending a b-day cake peace offering (to Kelly's mom, Sharon Osbourne). Well, that didn't work...

On Sunday (Oct. 27), Osbourne sent out these heated tweets:

@KellyOsbourne: "Not to be ungrateful but why would you send me a birthday cake via my MOTHER in a country half the would away? #JustSendItToME."

She continued:

@KellyOsbourne: "#EatMySh*t #Hypocrisy."

@KellyOsbourne: "#StefaniStopIt!" (aka, Mother Monster's real name is Stefani Joanne Angelica Germanotta).

@KellyOsbourne: "You are so far behind you think you are first!"

@KellyOsbourne: "I live for a #Cause not for the #Applause!!!!!!!"

@KellyOsbourne: "Guys, don't hate me, it's a guilty pleasure...like #SimplyRed!"

@KellyOsbourne: "I like desert, but i prefer the truth... it's sweeter."

@KellyOsbourne: "Let them eat cake' #MarieAntoinette."

Pretty intense stuff... Gaga has yet to respond.

Meanwhile, Kelly's own mom found the gift rather thoughtful:

‏@MrsSOsbourne: "Blown away by Lady Gaga's performance and graciousness."

So what do Mstars fans think... should Kelly just give it a rest?