There's something fishy about Lady Gaga's controversial mermaid in a wheelchair routine and Bette Midler has the answer.

The legendary performer is rolling out the punches over Gaga's latest performance and accusing her of copying her act.

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Taking to her Twitter page to set the record straight, The Divine Miss M made it clear there can only be one merwoman on wheels - and it's her!

"I'm not sure @ladygaga knows that I've performed my mermaid in a wheelchair for millions of people - and many of them are still alive," she wrote.

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"Dear @ladygaga if you think a mermaid in a wheelchair seems familiar - it's because it is! You can see it on youtube 24/7 - with ME performing it."

And she completed her war of words with an amusing warning.

"Dear @ladygaga I've been doing singing mermaid in a wheelchair since 1980 - You can keep the meat dress and the firecracker t*ts - mermaid's mine."

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