Katy Perry is hoping for a lazy Christmas of "eating and hibernating" as she rests up for her world tour.

The Roar hitmaker has spent the past few months travelling around the world promoting her latest album, Prism, so she has decided to make her Christmas holiday a rather low-key affair.

She says, "I have to rest during Christmas because I kick off my tour in May (14) and there's about three months of rehearsals and prep."

Joking about how much she consumes over the holiday, Perry adds, "I basically just eat and hibernate and eat and hibernate... and spontaneously pass out on the couch. It's a very normal Christmas."

And she isn't bothered about piling on a few pounds: "I've got muffin tops everywhere. My whole body is made of muffin tops."

Perry kicks off her Prismatic world tour in Belfast, Ireland on 7 May (14).