The 'Unconditionally' singer, 29, arrived at BBC Radio 2 studios (and later the KISS FM HQ) in London on a chilly Tuesday morning (10 December) clad in a black and mint striped mini dress, thigh high boots and furry jacket.
Katy has been in the UK for a few days performing at the weekend's Jingle Bell Ball and promoting her album Prism.
Her visit to England comes a few days after One Direction's Niall Horan denied reports he'd met up with Katy for dinner while they were both in New York.
Niall has made no secret of his admiration for Katy - who is loved up with musician John Mayer - and rightly so! She's the one who sent him through to Boot Camp when he auditioned for X Factor all those years ago when One Direction wasn't even around. (We know. Impossible to imagine such a world.)
While the pair appear to have become firm friends and have been snapped together a few times, it appears rumours of a dinner rendevezous in Manhattan last week are untrue.
Niall told Ryan Seacrest's KIIS-FM radio show of their hotel meeting: "I was in there and I think she was doing an interview or something and she was there and I was leaving and she left and we didn't have dinner or anything together. I just said, 'Hello' to her."
Well, we imagine plenty of Directioners would be more than happy with just a hello from Niall!
Katy and Niall - who jokingly proposed to Katy via Twitter earlier this year - could enjoy another rendezvous this weekend as both Katy and One Direction are booked to appear on The X Factor final.