Madonna: Lady Gaga Turned Down an Invitation to Perform With Me

Mama Monster has declined an invitation to perform with the Material Girl.

It's been a less than stellar year for diva-diva relations, especially between Madonna and Lady Gaga, who have spent the last 12 months trading snipes at one another at various concert stops around the globe.

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In her MDMA tour, Madonna includes a snippet of Gaga's "Born This Way" in her rendition of "Respect Yourself" -- a heavy wink at the similarity between the two songs. This after Madonna told an ABC interviewer last January that the Gaga composition sounded both familiar and "reductive.! "

But at a recent tour stop in St. Paul, Minn., Madonna says she holds no grudges against the next-generation pop star, and had even asked her to join her for a duet, according to The Huffington Post.

"I have the best fans in the whole world. So take that, Lady Gaga! Madonna told the crowd. You know, I invited her onstage to sing with me. But, she turned me down. It's okay. I've been rejected before. It builds a little character."

Madonna's last North American tour stop is Nov. 20 in Miami, then she takes off for the South American leg of her tour.