Katy Perry collapsed after a gas leak caused the 'American Idol' auditions to be evacuated.

Katy Perry

Katy Perry

The 'Never Really Over' hitmaker and her fellow judges - Luke Bryan and Lionel Richie - were just about to begin an audition when Katy detected a "pretty intense" gas smell and began to feel unwell, before the whole room had to be evacuated.

In a preview clip of Sunday's (23.02.20) episode obtained by People, Katy says: "Do you guys smell gas? It's pretty intense."

Luke then tells the producers of the show: "We're getting heavy propane."

And as she gets up to leave, Katy says: "I have a slight headache from it. Oh, it's bad. It's really bad."

Fire trucks and ambulances soon arrived on the scene and outside Luke insists: "This is not a joke, there really is a gas leak."

Katy then falls to the floor and says: "I'm not feeling good."

Meanwhile, the pop star and fellow judge Lionel have been joking about Katy's claim that he won't be invited to her wedding because he's too expensive.

The 'Roar' singer teased the 'Hello' hitmaker earlier this month when she said he and Luke wouldn't be getting invites to her upcoming ceremony to Orlando Bloom because she "couldn't afford" their appearance fee.

Now, Lionel has joked that he and Luke are outraged, as they keep asking Katy details about the wedding but get no response.

He quipped: "It's time that we just put it out there. Luke and I are just offended. We keep waiting for Katy like, 'OK, when is the date and where are we supposed to be and how many songs do you want us to sing?' Crickets. Crickets. OK.

"So we've kind of taken it to a point now where no, we're not invited. No, they don't want to see us."