By Laura Harding in London

Kylie Jenner has sported a diamond bra worth $US50 million ($A72 million) on the catwalk at the Victoria’s Secret fashion show.

The reality star and cosmetics mogul made a surprise appearance on the runway in Los Angeles, cheered on by boyfriend Timothee Chalamet and mother Kris Jenner.

Jenner wore the lingerie designed by jewellers Jacob & Co for the annual fashion event, using more than 4000 natural diamonds, as well as a huge yellow diamond.

The bra is described as “the most valuable Fantasy Bra ever made”.

“For four decades, Jacob & Co has created pieces that shouldn’t be possible,” the brand said in a statement.

“So when Victoria’s Secret asked us to re-imagine one of its most iconic creations, it started with a single question: what if there was no fabric at all?

“What began as a pencil sketch became a masterpiece of jewellery engineering. Crafted from 3218 individually designed components, the creation moves with the body like lingerie, combining the brilliance of high jewellery with the fluidity of fashion.

“More than 1000 hours to create. 15 artisans. 4410 natural diamonds.

“At its heart lies an extraordinary 75.54-carat natural Fancy Vivid Yellow diamond, surrounded by 4409 diamonds totalling 1373 carats, featuring an array of exceptional cuts, including Jacob & Co.’s signature Angel-Cut.

“Two icons, one shared belief: true spectacle should spark joy, inspire confidence and stir emotion.”

The Fantasy Bra is a staple of the annual lingerie show and is a piece of jewel-encrusted lingerie.

It is considered to be an honour to be chosen to model it.

Jenner teamed the bra with a large pair of angel wings, which are the signature look of Victoria’s Secret models, known as angels.

Other famous faces modelling lingerie on the catwalk included Gigi Hadid, Bella Hadid and Rosie Huntington-Whiteley.

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