Cara Delevingne and Sienna Miller
Cara Delevingne, was seen locking lips with Sienna Miller at the Met Ball in New York.

Supermodel Cara Delevingne has put her friendship with 'wifey' Rita Ora on the line after locking lips with Sienna Miller at the Met Ball.

In candid snaps taken at the annual event the 20-year-old Burberry beauty is shown snogging the British actress.

She later shared the racy image with fans on her Instragram and Twitter page along with the caption: "'Studded love! X"

The blonde duo are said to have struck up a bond after arriving to the A-List event with similar hairstyles and studding Burberry outfits.

The 5 ft 8 model and 31-year-old Miller were spotted laughing as they enjoyed each other's company.

But Ora is unlikely to happy about Delevingne having a new BFF.

The RIP hitmaker ,who swore off men following her bitter break-up with Kim Kardashian's younger brother Rob, has been spending quality time with bisexual Delevingne in recent months.

In March Ora revealed that she had taken the model off the market.

"She's [Cara] officially mine. She's, like, untouchable. I've taken her off the market. We call each other 'wifey'," she told The Sun.

"You know what a wifey means? It's like your other half. Like when you get married."

Delevingne is under investigation by H&M after a plastic bag containing a white substance fell out from her bag as she as looked for the keys to her Belgravia home.

The high street brand, whoch has a "zero tolerance" policy to drugs, unveiled the blonde beauty as the face of its Divided clothes range this year.

They have confirmed that they will drop the star if they find she has been using illegal substances.

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