"So happy that my bubba @caradelevingne is in town even if it is just for a night!" she captioned the photo, in which the pair sport matching temporary heart tattoos.
Cara also shared Kelly's photo on her own Instagram page. "Reunited at last," the young supermodel captioned the image.
The pair were first spotted hanging out at the 2013 Punk-themed Met Ball, where they posed alongside fellow celebrity friends Miley Cyrus and Rita Ora. Since then they have been spotted together at various industry events, and have reportedly become very close friends.
When Cara launched her collection of bags for Mulberry, the Cara Delevingne Collection, during London Fashion Week in February, Kelly stepped out to support her friend during the event at the Claridge's hotel.
Wearing a sleek black dress, she was seen laughing throughout the night with Nick Grimshaw, having fun while checking out the new range of bags.
It's been a busy few weeks for Cara, who closed the Chanel show during Paris Fashion Week, and who is also set to make her TV acting debut in the one-off drama Timeless for Sky Arts Playhouse Present series. "It's a really touching story," said the stunning 21-year-old. "I'm really honoured to be working with Sylvia in a one-off production for Playhouse Presents."