On Sunday, former Illinois Rep. Joe Walsh addressed his role in stirring racist rhetoric in politics in the past while announcing his intentions of challenging President Donald Trump in the Republican primary.

Walsh apologized for his past comments during an appearance on ABC's "This Week with George Stephanopoulos" in which he said he had a role in Trump's ascension.

“I helped create Trump, there’s no doubt about that,” he said.

Walsh went on to offer his opinion of Trump: “He’s nuts, he’s erratic, he’s cruel, he stokes bigotry.”

He also wrote in a recent New York Times op-ed that Trump “inspires imitators” but brought up his own “share of controversy.”

“At times, I expressed hate for my political opponents. We now see where this can lead,” he wrote. “There’s no place in our politics for personal attacks like that, and I regret making them.”

Walsh's past comments

In 2014, Walsh was pulled off the air during his radio show for using racist slurs. He also promoted the "birther" conspiracy during former President Barack Obama's time in office and said Obama was only elected because he is black.

More:Former Illinois Rep. Joe Walsh announces he will challenge Trump in Republican primary

When asked by Stephanopoulos on Sunday to address instances of his own racism, including his promotion of the false conspiracy that Obama is Muslim and remarks against Sen. Kamala Harris, Walsh said he has reflected on his previous statements.

“I said some ugly things about President Obama that I regret,” Walsh said.

In 2017, Walsh tweeted “We LOWERED the bar for Obama. He was held to a lower standard cuz he was black.”

“I had strong policy disagreements with Barack Obama, and too often I let those policy disagreements get personal,” he said Sunday.

He's been all over the place on Trump's comments

Walsh has a history of inconsistency in his opinions of Trump’s rhetoric. At times, he has denounced the president as a racist. This summer when Trump told four Democratic congresswomen, who are people of color and citizens of the U.S., to “go back and help fix” the countries he said they “originally came” from before trying to make legislative changes in the USA, Walsh spoke out.

“To say 'go back to where you came from' is gross. It’s offensive, ignorant, anti-American, and racist,” Walsh tweeted.

But it was not that long ago that Walsh thought Trump’s language made him a bully, but not a racist, and that Walsh was still making racist claims about Obama:

Why he's apologizing

Walsh said the one good thing about Trump's language since he has been in office is that Trump has made him realize his attacks were inappropriate. The difference between them?

“We have a guy in the White House who’s never apologized for anything he’s done or said. I think it’s a weakness not to apologize," Walsh told Stephanopoulos. "I helped create Trump, there’s no doubt about that. The personal, ugly politics, I regret that and I’m sorry for that. And now we’ve got a guy in the White House, George, that’s all he does.”