Gaga reckons that Kelly's show, which sees her pick apart various celebrities outfits, is "rooted in criticism and judgement."
In full, Gaga wrote the following to Kelly:
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"Everyday, through my music and public voice I choose to be positive and work towards a kinder and braver world with our community of followers."
Excellent, good for you Gaga etc.
"I encourage them to ignore criticism, stand up to bullies, know their own value and see that we are all the same and no one person is worth more than another."
Again, very brilliant.
"I have empathy for you Kelly, but I feel it culturally important to note that you have chosen a less compassionate path."
In other words, Gaga reckons Kel's career choice is MEAN and hers is GREAT.
She goes on: "Your work on E! with the Fashion Police is rooted in criticism, judgment, and rating people's beauty against one another."
"“Appearance” is the most used reason for bullying in the world. Your show breeds negativity, and over the years has even become comedic in nature."
Oh. Em. Actual. Gee.
And it goes ON, saying: "It glorifies you and Joan Rivers pointing in the camera, laughing, and making jokes about artists and celebrities as if we are zoo animals."
In closing, Gaga said: "I cannot control my fans, and I discourage them from any negativity and violence, because that is wrong and hurtful - and I do feel baldy that your feelings were hurt.
"However, we can all do our part in the media to set a standard of respect, compassion, and love."
Now, while Kelly maintained a dignified silence it was her MUM, Sharon Osbourne who then got all involved defending Kelly's honour.
Sharon wrote back an open letter of her very own, which makes for excellent reading.
"By your actions to Kelly right now, you have shown me that you are nothing more than a publicly seeking hypocrite and an attention seeker. You know it would have been much more dignified of you to do this privately.
"I am calling you a bully because you have 32 million followers hanging on your every word and you are criticizing Kelly in your open letter. Are you so desperate that you needed to make this public?"
Sharon added: "A word from you would stop all the hideous, negative and vile threats from your 'little monsters.'"
A while back, Kelly revealed in a magazine interview that she has received threats from Gaga fans after calling them 'the worst'.
Shazza signed off her letter, saying: "Let me know if you want to continue this debate. I’m an open playing field for you my darling."
Over to you Gaga!