What's Katy Perry's hidden talent?

Singer Charli XCX says Katy Perry has a hidden talent - the pop star can undo a brassiere through a T-shirt.

The "Boom Clap" hitmaker discovered Perry's skill when the "Roar" singer unhooked her brassiere as they hung out backstage when Charli supported Perry on her Prismatic World Tour, reports femalefirst.co.uk.

"Supporting Katy was fun. She made me a chicken salad one day and she undid my bra on the last day through my T-shirt. It was very skilful. We were just talking in the corridor.

"I thought she was giving me a back massage. I was like, 'This is really nice,' and then she undid my bra. I was, like, 'Oh cool'," Charli said during an interview with The Hits radio.