Lady GaGa turned down the opportunity to perform with Madonna.
Madge had asked Gaga if she wanted to join her on stage in their hometown of New York for her current world tour. But Gaga was forced to decline because she has "prior commitments" with her own "Born This Way Ball" world tour.
Gaga's manager said: "Madonna called to ask GaGa to perform with her at Yankee Stadium. Her manager reached out to us and said Madonna would like GaGa to perform with her. She really wished she could do it. She said, 'If we do it, let's donate the money to charity'. But GaGa's committed to her own tour."
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