Katy Perry sure pushed the envelope when it came to her cleavage-baring mint green Gucci gown at Sunday's Grammys, and no one was more aware of her fashion choice than Ellen DeGeneres. "Here I am taking a tasteful glance at Katy Perry's dress," the talk show host, 28, tweeted during music's biggest night Feb. 10, along with a picture of herself, mouth agape, posing with Perry and DeGeneres' wife, Portia de Rossi.

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Daring to bare despite an email sent from Grammy network CBS instructing show guests to "be sure that buttocks and female breasts are covered," the "Wide Awake" singer turned heads in her form-fitting gown that featured a prominent cutout to display her cleavage.

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"I was inspired by Priscilla Presley in the '70s . . . Married to Elvis Presley, of course." Perry -- who attended the show with Girls' Allison Williams, sat with boyfriend John Mayer and celebrated a nomination for Best Pop Solo Performance -- told E! News. "The bigger the hair the closer to God."

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Perry wasn't the only one who made a daring fashion statement on Sunday. When presenting the night's first award, Pitbull joked that Jennifer Lopez -- who famously chose a plunging green Versace gown for the 2000 Grammys and followed suit Sunday with a leg-baring black ensemble -- inspired CBS' now-infamous memo.

"They didn't say anything about leg!" Lopez, 43, protested, when defending her Anthony Zacarello gown to Ryan Seacrest on the red carpet. "I thought I was being such good girl -- [just] a little shoulder and a little leg."

This article originally appeared on Usmagazine.com: Ellen DeGeneres Stares at Katy Perry's Cleavage During Grammys: Picture