Jessie was booked in to perform in the Live Lounge but managed to squeeze in a quick picture with Fearne before taking to the microphone.
The photo shows Jessie with her new, slightly longer hairstyle standing next to DJ Fearne - who is pulling her best pout!
Radio 1 officials then tweeted the picture, saying: "A cheeky little selfie before the special @JessieJ #R1LiveLounge."
Fearne later commented: "Watching @JessieJ singing today in the #R1livelounge was captivating. I think its impossible for her to hit a bum note. She's top of her game."
Earlier, former Voice mentor Jessie was snapped as she arrived at the radio station in central London.
The star was all smiles as she headed inside the building, wearing leather leggings, a black T-shirt and chunky black boots.
She topped off her outfit with a dark purple jacket, her favourite gold hoop earrings and she carried a black patent bag.
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