Lady Gaga Reveals She Posed Nude for Tony Bennett

During Lady Gaga's 90-minute Thanksgiving special, A Very Gaga Thanksgiving, which the singer conceived and directed, she revealed some unexpected news.

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She stripped down so that Tony Bennett could sketch pictures of her for an upcoming issue of Vanity Fair magazine that would be released next year. The idea was thought up by photographer Annie Leibovitz.

"I walked in and said, 'Well Tony, here we are' and I dropped my robe and I got into position," the singer explained. "I felt shy and thought, 'It's Tony Bennett, why am I naked?' "

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It wasn't a random occurrence. Gaga, 25, and Bennett, 85, recorded "The Lady Is a Tramp" together for Bennett's Duets II album. The special opened with the duo's performance of that same track.

Gaga later praised Bennett, saying, "He's so handsome. I feel terrible whenever his wife is around because he's so charming and such a gentleman."

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Bennett had similarly positive words to say. "She is the most beautiful person I ever met but there is something special about her."

Gaga was also interviewed by Katie Couric, touching on her personal life, romances and why she doesn't talk about her love life. She performed a slew of her hits, including "Born This Way" and "Edge of Glory."

It's been a busy week for Gaga, who unveiled Gaga's Workshop at Barneys earlier this week and released a new book.