CNN anchor Don Lemon was absolutely beside himself on Monday night after CNN political commentator Rick Santorum showed no contrition during his first on-air appearance after his offensive remarks about Native American culture. Apologizing to viewers, Lemon said it was “horrible and insulting” that Santorum tried to “whitewash” his comments.

Santorum sparked intense backlash last month when he claimed that “there isn’t much Native American culture in American culture” during a speech for a right-wing student organization. The former Pennsylvania senator also claimed Christian European settlers “birthed a nation from nothing” and that “there was nothing” in America before their arrival.

Despite calls from Native American groups for CNN to fire Santorum, the network did not provide any public statement about Santorum or his remarks. Instead, CNN pointed media outlets to an outside spokesperson for the ex-senator, who said Santorum “had no intention of minimizing or in any way devaluing Native American culture.”

Just days after the controversy, Santorum made his on-air return during a panel discussion on Cuomo Prime Time. Initially brought on to discuss the state of the Republican Party, Santorum was eventually confronted about his comments by anchor Chris Cuomo.

“This seemed like you were trying to erase diversity in the interest of some white Christian right,” Cuomo said, prompting Santorum to claim he “misspoke” and was just talking about the founding documents of this country.

“You have done this with homosexuality—comparing it to bestiality—same-sex marriage, minorities,” Cuomo further noted as Santorum let out a long groan.

“If you looked at the whole speech, I was talking to a group of young people about the founding of the country and the importance of religious liberty in the country. It was all about the Founders,” Santorum insisted, adding that his comments were taken “out of context.”

Moments later, during the handoff between Cuomo’s and Lemon’s shows, an irate Lemon unleashed a passionate and angry tirade over Santorum’s lack of contrition and the likelihood that the conservative pundit will face no repercussions.

“I was furious watching that interview in my office. I cannot believe the first words out of his mouth weren’t ‘I’m sorry, I said something ignorant, I need to learn about the history of this country,’” the CNN anchor seethed. “No contrition! Didn’t talk about the suffering that Native Americans have had to deal with in this country.”

“Did he actually think it was a good idea for him to come on television and try to whitewash the whitewash that he whitewashed?!” Lemon exclaimed. “It was horrible and insulting! And I apologize to the viewers who were insulted by it. I was sitting in my office furious because he’s done it so many times! So many times!”

Cuomo then made an attempt both to rationalize Santorum’s behavior and defend bringing the former lawmaker on his show, two things Lemon appeared to be in no mood for.

“I had him on because I want people to see what this is. There is no mystery for you guys,” Cuomo declared.

“People know what it is,” Lemon fired back.

After a bit of a back-and-forth over the merits of giving someone like Santorum airtime, during which Cuomo accused Lemon of wanting to “censor” the right-wing pundit, Lemon finally seemed to have had enough.

“We gotta go because we are not going to agree,” Lemon said tersely.

“I agree because I know where you are coming from and I love you, Don Lemon. We agree on the problem. What’s the solution? We’ve got to figure it out,” Cuomo responded.

“Oh, I’ve got a solution, but anyways, not my decision,” Lemon quickly shot back.