Carly Rae Jepsen will be Katy Perry's Witness in 2018, when the EMOTION singer joins Perry on her headlining tour.

Speaking to Entertainment Tonight at the premiere of Leap! in Los Angeles on Saturday (August 19), the Canadian pop star dished on how she got invited to join Perry on tour.

"Her people call[ed] my people. It was nice and I've obviously known her throughout the years and we get along great. So it'll be a lot of fun I'm sure," Jepsen gushed. "I'm sure the wait will be well [worth] it."

Jepsen, who will open for Perry between January 5 and February 5, also opened up about what she likes to bring on tour with her.

"I do a lot of writing when I'm on the road, so I always have a little acoustic guitar with me and [a] recording gear set up, like those mini microphones and, I don't know, you can make a back of the bus studio if you really have all the pieces," she explained. "So that would be number one. And number two, I think, [a] really good, fun, light book to read. I usually go for, like, the old period pieces."

What's she's looking forward to the most, however, is getting "some hangs" in with Perry.

"We definitely have had some fun nights before," she teased. "Tours [are] always busy. You never know how much time you have off to rest your voice, but if we can get in some partying at the end, I'm just, we will!"

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