Former U.S. president Donald Trump, the oldest candidate in the 2024 GOP presidential field, said there should not be an age limit for the presidency but expressed support for requiring mental competency tests for candidates.

鈥淚鈥檓 all for the tests,鈥 Trump told NBC鈥檚 Kristen Welker in an interview clip that aired Saturday, citing a cognitive test he took in 2020 at Walter Reed National Military Medical Center. 鈥淚 aced it. I get everything right.鈥

But the former president, 77, cast doubt on the practicality of requiring such a test, adding, 鈥淎 lot of people say it鈥檚 not constitutional to do it.鈥

Trump鈥檚 comments come as he considerably leads the Republican presidential pool to face President Joe Biden 鈥 who is 80 鈥 in 2024.

When asked if there is a need for a new generation to take the helm, Trump said, 鈥淚t鈥檚 always time for a new generation.鈥

But, he added, 鈥淪ome of the greatest world leaders have been in their 80s,鈥 though the 77-year-old quickly clarified that he鈥檚 鈥渘ot anywhere very near 80, by the way.鈥

The ages of the incumbent and the GOP front-runner have raised questions about whether they are fit for office, and other presidential candidates have used the issue to argue that they will not be effective leaders.

Former vice-president Mike Pence, who is challenging his former boss for the GOP presidential nomination, told CNN in an interview that aired Sunday, 鈥淲e don鈥檛 need a president whose too old and we don鈥檛 need a president whose too young.鈥 But he stopped short of saying whether 77 is too old to be president.

鈥淚 think that鈥檚 a judgment for voters,鈥 Pence told CNN鈥檚 Jake Tapper on 鈥淪tate of the Union.鈥 鈥淚 trust voters to make their decision, whether it be the mental competency of people or whether it be their age or energy level.鈥

But Trump said the problem with his successor is 鈥渂igger鈥 than his age.

鈥淚 don鈥檛 think Biden is too old, but I think he is incompetent,鈥 Trump said. 鈥淎nd that鈥檚 a bigger problem.鈥

Biden, who would be 82 at the start of his next term if reelected, has also shrugged off concerns about his age in recent months. When asked why an 82-year-old would be the best fit for president, that he has 鈥渁cquired a hell of a lot of wisdom.鈥

鈥淚鈥檓 more experienced than anybody (who鈥檚) ever run for the office,鈥 he said, adding that he thinks he鈥檚 proven himself to be effective.

However, a showed that roughly three-quarters of Americans say they鈥檙e seriously concerned that Biden鈥檚 age might negatively affect his current level of physical and mental competence and his ability to serve out another term if reelected.

This story has been updated with additional information Sunday.