Sen. Mitt Romney, R-Utah, used President Biden's own words against him on Wednesday while calling on him to drop his 2024 bid for re-election and join him in retirement at the end of his term.

Romney's challenge to Biden comes just hours after the first-term senator officially announced he would not be seeking a second term, citing his own advanced age as his main reason for the decision.

"President Biden, when he was running, said he was a transitional figure to the next generation. Well, time to transition," Romney said when asked by a reporter if his decision not to run for re-election because of his age should also apply to Biden, 80, and former President Donald Trump, 77.

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Republican Utah Sen. Mitt Romney

Sen. Mitt Romney, R-Utah, speaks to the media about not running for a second Senate term in his office in the Russell Senate Office Building in Washington on Wednesday. September 13, 2023. (Bill Clark/CQ-Roll Call, Inc via Getty Images)

Romney's comments were in reference to Biden calling himself a "transition candidate" during his 2020 campaign for the presidency, something he later meant he would be someone who would help pave the way for a new generation of Democratic leadership.

"I think it would be a great thing if both President Biden and former President Trump were to stand aside and let their respective party pick someone in the next generation … I think both parties would be far better served if they were going to be represented by people other than those of us from the baby boom generation," he added.

Concern over Biden's age amid his re-election has continued to grow, even from within his own party. A recent Associated Press-NORC poll found 69% of Democrats think Biden is too old to run again.

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Joe Biden and Mitt Romney

President Joe Biden and Republican Utah Sen. Mitt Romney. (Getty Images)

Romney's inclusion of Trump in his concern about the age of the two presidential front-runners joins that of Trump's closest rival in the Republican primary, Florida Gov. Ron DeSantis, who said during a recent interview on CBS that the former president's age was "a legitimate concern" for voters going into 2024.

The Biden campaign did not immediately respond to Fox News Digital's request for comment.

Former President Donald Trump

Republican presidential candidate former President Donald Trump arrives at the Monument Leaders Rally hosted by the South Dakota Republican Party on September 08, 2023, in Rapid City, South Dakota. (Scott Olson/Getty Images)

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