Kim Kardashian was 'determined to fit' Marilyn Monroe’s iconic dress for the Met Gala: 'I had to lose 16 pounds'

Kim Kardashian closed out the Met Gala red carpet on Monday night while wearing Marilyn Monroe's dress from 1962.

The reality television star and mogul's appearance was much anticipated after rumors began to swirl about her look. And in true Kardashian fashion, she exceeded expectations when she arrived in the gold dress that Monroe wore while singing "Happy Birthday" to President John F. Kennedy.

"It's 60 years old," Kardashian told La La Anthony during Vogue's live red carpet coverage. "I had this idea to put it on and try it on and then they came with armed guards and gloves. I tried it on and it didn’t fit me."

While the dress by costume designer Jean-Louis was first commissioned for Monroe at $1,440, it was later sold for over a million dollars as a part of the actress's estate sale in 1999. In 2016, it was sold at Julien's Auctions for $4.8 million and acquired by Ripley's Believe It Or Not Museum.

"I’m a big fan of auctions and I own several JFK pieces so I know the owner of Julien’s. He was able to connect me [with Ripley’s] and that’s how the conversation started," Kardashian told Vogue during an exclusive interview on Sunday evening.

Ripley's eventually agreed to loan the dress to Kardashian and flew it out to her home in Calabasas to try. The original fitting didn't go as planned.

“I always thought she was extremely curvy. I imagined I might be smaller in some places where she was bigger and bigger in places where she was smaller. So when it didn’t fit me I wanted to cry because it can’t be altered at all," Kardashian told the publication.

When it came to planning a backup look, she refused to even consider the idea. "It was this or nothing," she said, explaining that she needed to wear "the original naked dress," and was set on doing whatever it took to make it happen.

"I had to lose 16 pounds down today to be able to fit this," she said while chatting with Anthony. "It was like a role. I was determined to fit it."

She also told the publication about the strenuous diet and exercise plan she adhered to in order to make that happen.

"I would wear a sauna suit twice a day, run on the treadmill, completely cut out all sugar and all carbs, and just eat the cleanest veggies and protein," she said. "I didn’t starve myself, but I was so strict."

One month later, she had another fitting. "I wanted to cry tears of joy when it went up."

Kardashian dedicated herself to the look in other ways, including spending the day prior to the event dyeing her hair platinum blonde like Monroe's. "I’m spending the whole day just dyeing my hair, 14 hours straight," she said.

She also had to make adjustments to her regular routine of getting ready before stepping onto the stairs of the Metropolitan Museum of Art — most notably, arriving to the museum in a dressing gown to put the dress on in a private fitting room.

"I’m extremely respectful to the dress and what it means to American history. I would never want to sit in it or eat in it or have any risk of any damage to it and I won’t be wearing the kind of body makeup I usually do," she said. "Everything had to be specifically timed and I had to practice walking up the stairs."

Kardashian's shocking moment was complete when she arrived arm-in-arm with her boyfriend Pete Davidson, just days after making their red carpet debut as a couple at the White House Correspondents' Dinner. He even helped her up the steps and planned the perfect post-gala meal after Kardashian has spent weeks dieting.

"Since I haven’t eaten carbs or sugar in about three weeks we’re eating pizza and donut party back at the hotel," Kardashian told Anthony.

And while Kardashian plans on remaining blonde for a while, she'll soon be ditching Monroe's dress in favor of some replicas to wear throughout the night.

"I have a replica of the dress she wore to the Oscars in 1962," she told Vogue, noting that it might be her outfit of choice for the hotel room pizza party.

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