Former President Trump opposed the idea of age limits for U.S. politicians but said mental competency tests would be a "good idea."

Trump made the comments in an interview with NBC's "Meet the Press," which aired Sunday. Host Kristen Welker pressed Trump on age limits, gaining steam as Trump, 77, and President Biden, 80, appear likely to square off in the 2024 presidential election.

"You know, I took a test two years ago, three years ago. And as the doctors said — and it was in front of doctors and a whole big deal at Walter Reed, which is an incredible place. And I aced it. I get everything right. I’m all for testing. I frankly think testing would be a good thing," Trump told Welker.

Trump asserted that some people argue an age limit or cognitive test would be "unconstitutional," though he said he wasn't sure.

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Donald Trump

Trump says he is nowhere "near 80," despite the fact that he would turn 80 years old within 18 months of gaining office if he wins re-election in 2024. (Photo by JOSEPH PREZIOSO/AFP via Getty Images)

"[You] know, some of the greatest world leaders have been in their 80s. I’m not anywhere very near 80, by the way," Trump claimed. "I don’t think Biden’s too old, but I think he’s incompetent, and that’s a bigger problem."

Trump would turn 80 years old within 18 months of gaining office if he wins re-election. Meanwhile, Biden would be 82 at the start of his second term.

Biden has faced far more scrutiny about his age due to his frequent lapses in memory and stammering speeches.

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Joe Biden standing in front of an American flag

President Biden delivers remarks at Prince George's Community College on September 14, 2023 in Largo, Maryland. (Kevin Dietsch/Getty Images)

Former South Carolina Gov. Nikki Haley has played a major role in pressing for cognitive tests for U.S. politicians across the board. While she has not endorsed an age limit, she has called for legislation requiring presidential candidates and members of Congress to pass competency tests if they are over 75.

Haley mocked the U.S. Senate as "the most privileged nursing home in the country" earlier this month following health scares from Senate minority leader Mitch McConnell and Sen. Dianne Feinstein, D-Calif.

"It's sad," she told Fox News following McConnell's second freezing episode. "No one should feel good about seeing that any more than we should feel good about seeing Dianne Feinstein, any more than we should feel good about what’s happening or seeing Joe Biden’s decline."

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Nikki Haley

Former South Carolina Gov. Nikki Haley has played a major role in pressing for cognitive tests for U.S. politicians across the board. (Rachel Mummey/Bloomberg via Getty Image)

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Haley is challenging Trump in the 2024 Republican Presidential Primary, though Trump maintains a dominant lead over all the other candidates in polls. Trump told Welker on Sunday that he likes the "concept" of a female vice president running with him but that he would ultimately "pick the best person."