On a very chilly morning in the capital, the 'Bang Bang' singer, 21, was seen sauntering up to the radio studios in nothing but a tiny slip of a white lacy crop top and skirt.
Ariana was clutching a rather cosy looking fluffy coat but not actually wearing it. Maybe to give us all a good look at her angelic outfit? Or her California tan?!
Either way, we feel cold looking at her!
Despite no doubt feeling the cold, the singer made sure to stop and chat to the fans that had gathered outside the radio studios, taking pictures and signing autographs.
Let's hope Ariana doesn't fall ill ahead of tomorrow night, as she'll be joining Taylor Swift and Ed Sheeran in performing at the Victoria's Secret Fashion Show at Earl's Court Exhibition Centre.
For the first time ever, the Victoria's Secret extravaganza is being filmed in the UK, with models including Alessandra Ambrosio and Adriana Lima strutting the catwalk as Taylor, Ariana and Ed provide the musical accompaniment.
Ariana will also be back on our shores performing next year, as she brings her 'Honeymoon World Tour' to the UK. So far, she's announced dates in London, Manchester, Glasgow and Birmingham.
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