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Story highlights

"I don't know about the Hitler comparison," Donald Trump said Tuesday

Comedian Louis C.K. on Trump: "It was funny for a little while. But the guy is Hitler."

(CNN) —  

Donald Trump on Tuesday addressed criticism of a new practice at his rallies that has been compared to the “Heil” salute from Nazi Germany, dismissing the controversy as “ridiculous” before saying he would look into ending it.

“I don’t know about the Hitler comparison. I hadn’t heard that, but it’s a terrible comparison. I’m not happy about that certainly,” Trump said on ABC’s “Good Morning America.”

Recently, Trump has started asking voters to raise their right hand and pledge to support him – creating an image that some have argued evokes the rise of Adolf Hitler, particularly when coupled with his sharp rhetoric toward minority groups like Mexicans and Muslims.

READ: A Trump presidency doesn’t worry Pakistan, top official says

Hitler comparisons are not new for Trump. Comedian Louis C.K., in a postscript to a Saturday email about the latest episode of his web series “Horace and Pete,” he asked fans and readers to “please stop it with voting for Trump.”

“It was funny for a little while,” he wrote. “But the guy is Hitler. And by that I mean that we are being Germany in the 30s.”

Former Mexican President Vicente Fox, a spirited Trump detractor, said last month that the GOP front-runner “reminds me of Hitler.”

Anne Frank’s stepsister, in a January essay to mark International Holocaust Remembrance Day, accused Trump of “acting like another Hitler.”

READ: Louis C.K.: ‘Insane bigot’ Donald Trump ‘is Hitler’

Before that, former New Jersey Gov. Christine Todd Whitman, a Republican, told CNN’s Alisyn Camerota on “New Day” that his plan to halt the immigration of Muslims into the U.S. reminded her of “the kind of rhetoric that allowed Hitler to move forward.”

Trump has dismissed such comparisons in the past. When a Philadelphia newspaper made the comparison on its cover last December, Trump, told CNN it was “just another paper going out of business.”

When ABC News asked him directly about the comparisons in the context of his plan to ban Muslim travel to the U.S., Trump said he was acting more like Franklin Roosevelt than Hitler.

On Tuesday, Trump continued his deflections. During an interview on “The Today Show” on NBC, host Matt Lauer asked Trump to consider the historical context of the image.

The Republican front-runner at first dismissed the controversial comparison, calling it “ridiculous” and “a big stretch,” and insisting rally attendees were just “having fun.”

“Well, I think it’s ridiculous, I mean we’re having such a great time,” Trump said. “Sometimes we’ll do it for fun, and they’ll start screaming at me, ‘do the swear-in, do the swear-in!’ “

“Honestly until this phone call, I didn’t know it was a problem,” he added. “That this would be brought up this morning, I’m surprised to hear it.”

But pressed if he would stop asking supporters to make the pledge now that he was aware of the controversy, Trump said, “Well, I’ll certainly look into it.”

“I mean I’d like to find out that that’s true, but I would certainly look into it, because I don’t want to offend anybody. But I can tell you that it’s been amazingly received, but I will certainly look into that.”

Trump also discussed the issue in an interview on MSNBC’s “Morning Joe.”

“I say jokingly, ‘Raise your hand if you swear to endorse me,’ ” he said. “The entire place is practically laughing and having a good time. They’re raising their hands in the form of a vote, not in the form of a salute.”