Fox News host Greta Van Susteren has called on her colleague Chris Wallace to apologize after making body-shaming comments about Kelly Clarkson's weight.

Wallace made the comments while appearing on Friday on "The Mike Gallagher Show." Wallace and Gallagher were joking about Gallagher's weight, when Gallagher made the initial comments about Clarkson.

"Listen, don't fat shame me. You do a lot of fat shaming," Gallagher said, according to audio acquired by Media Matters. "That's the new phrase now, 'fat shaming.' Have you seen Kelly Clarkson? You know the singer, Kelly Clarkson? Holy cow, did she blow up."

Wallace initially replied, "Really? Do we want to talk about some of your friends?" He added, "Kelly Clarkson's got a lovely voice."

He wasn't able to hold back from making an offensive comment about Clarkson's weight, however. "She could stay off the deep dish pizza for a little while."

Van Susteren went on her blog to express her disgust at Wallace's comment. "This 'guy snickering' about her weight is obnoxious. He should apologize," she wrote.

Neither Clarkson and Wallace have officially commented as of press time, but on Friday Clarkson appeared on "Ellen" to discuss criticism of her weight in popular culture.

"I think what hurts my feelings for people is that I'll have a meet-and-greet after the show and a girl who's like bigger than me will be in the meet-and-greet and be like, 'Wow, if they think you’re big I must be so fat to them.' And it's like, you're just who you are," Clarkson said.