Is Kidman defying gravity?
Nicole Kidman in Melbourne last week. Picture: Getty Images

Several days after she walked the red carpet in a revealing low-cut dress, rumours continue to swirl that Nicole Kidman has gone under the knife to amp up her cleavage.

The Oscar-winning actress stepped out alongside husband Keith Urban for the Celebrate Life Ball in Melbourne on Friday wearing a daring pink Prada gown that showed off her perky decolletage, leading commentators to suggest she had enhanced her assets with a boob job in recent months.

Watchers pointed out the 46-year-old's bust seemed to defy the effects of gravity, comparing photos of her in 1999 cult flick Eyes Wide Shut, where she was sporting a significantly smaller chest, to the new snaps.

"Famously flat-chested, Nicole's boobs certainly look like they've had a boost," Laura Casewell, editor of The Cosmetic Surgery Guide, told Britain's Daily Mirror.

"They not only look bigger but also much more rounded, which indicates she's had breast implants."

However, others are maintaining it was simply an optical illusion thanks to hidden padding in the dress.

Nicole Kidman with former husband Tom Cruise in 1994. Picture: WireImage

A representative for the mother of four had no comment when contacted about whether Kidman had undergone a breast augmentation.

It's not the first time Kidman has had to address cosmetic surgery rumours, with the star emerging at the Cannes Film Festival last month to promote her latest film Grace of Monaco with a strangely puffy face and lips.

A number of plastic surgeons weighed in on the debate, saying her lips looked "heavy and unnatural" and that her doctor had gone too far.

But last year, Kidman insisted she was "completely natural" and had only tried a wrinkle-freezing Botox treatment once.

"No surgery for me; I did try Botox, unfortunately, but I got out of it and now I can finally move my face again," Kidman told an Italian newspaper.

Nicole Kidman's body appears to have undergone a big overhaul. Picture: Getty Images

The West Australian

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