Acting White House chief of staff Mick Mulvaney said Sunday that the New Zealand mosque massacre, where a white supremacist allegedly killed 50 people, had nothing to do with President Donald Trump's rhetoric and that the president "is not a white supremacist."

Mulvaney defended Trump during a pair of interviews on the Sunday political talk shows.

On "Fox News Sunday," anchor Chris Wallace asked "to the degree that there's an issue with white supremacist, white nationalist, anti-Muslim bigotry in this country, and there is an issue with that, why not deliver a speech condemning it?"

"You've seen the president stand up for religious liberty, individual liberty," Mulvaney said. "The president is not a white supremacist. I'm not sure how many times we have to say that. And to simply ask the question, every time something like this happens overseas, or even domestically, to say, 'Oh, my goodness, it must somehow be the president's fault,' speaks to a politicization of everything that I think is undermining sort of the institutions that we have in the country today."

"Let's take what happened in New Zealand yesterday for what it is, a terrible, evil, tragic act, and figure out why those things are becoming more prevalent in the world," he continued. "Is it Donald Trump? Absolutely not. Is there something else happening in our culture where people go, 'Know what? I think today I'm going to go on TV and live-stream me murdering other people'? That's what we should be talking about. Not the politics of the United States."

Trump condemned the shooting on Friday, but when asked if he believes white nationalist terrorism and violence is a rising concern globally, the president said, said, "I don't really." Trump added that he thinks "it's a small group of people that have very, very serious problems."

On Monday morning, Trump tweeted, "The Fake News Media is working overtime to blame me for the horrible attack in New Zealand. They will have to work very hard to prove that one. So Ridiculous!"

There have been several white nationalist or white supremacist attacks in the U.S. over the past few years, including the massacre of 11 worshippers at a Pittsburgh synagogue last fall and the murder of nine black churchgoers at a congregation in Charleston, South Carolina, in 2015.

The alleged New Zealand shooter, in an apparent manifesto that was revealed after the shooting, wrote that he was a Trump supporter "as a symbol of renewed identity and common purpose," although he said he disagreed with his policies.

"I don't think it's fair to cast this person as a supporter of Donald Trump any more than it is to look at his — sort of his eco-terrorist passages in that manifesto that align him with Nancy Pelosi or Ms. [Alexandria] Ocasio-Cortez," Mulvaney said. "This was a disturbed individual, an evil person, and to try and tie him to an American politician from either party probably ignores some of the deeper, difficulties that this sort of activity exposes."

Mulvaney later said Trump "is doing everything that we can to make it clear, look, this has to stop."

On CBS's "Face the Nation," Mulvaney said Trump "is no more to blame for what happened in New Zealand than Mark Zuckerberg is because he created Facebook." The social networking site said it removed 1.5 million videos of the shooting within 24 hours of the attack.

Trump's former homeland security adviser, Tom Bossert, said on ABC's "This Week" that he hoped the president "doesn't maintain the position" that white nationalism is "not a threat at all."

"I don't think that the two threats are equal, ISIS and white supremacists," Bossert said. "They're equally repugnant. They are not equal in size. But the president has to combat the ideology of both."

Sen. Amy Klobuchar, D-Minn., said on CNN's "State of the Union," that white nationalists are "using" Trump "as an excuse" to commit violence.

Trump "should be giving strong statements, public speeches defending Muslims in this world,” the 2020 presidential candidate said.