US President Joe Biden turned 81 on Monday (November 20), a milestone that drew attention to his status as the oldest person to ever occupy the Oval Office, with opinion polls showing Americans worried he is too old for the post he is seeking re-election to.

White House press secretary Karine Jean-Pierre told reporters that Biden and his family would celebrate his birthday later this week with coconut cake when they gather for the Thanksgiving holiday on the island of Nantucket.

Biden has addressed those who worry that he is too old for the rigors of the White House with humor and an attempt to convince voters that his age and experience over a half-century in public life is an asset in tackling America's problems. At a ceremony on Monday to pardon the National Thanksgiving Turkey, Biden joked that he was not around for the first such turkey event 76 years ago.

If re-elected, Biden would be 86 by the end of his second term in office. Republican Ronald Reagan, who had the prior record as oldest US president, ended his second four-year term at age 77 in 1989. Trump, the frontrunner for the Republican nomination to challenge Biden in the 2024 election, is 77.

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In a mid-September Reuters/Ipsos poll, voters expressed concern over Biden’s age and his fitness for office. Seventy-seven percent of respondents, including 65 percent of Democrats, said Biden is too old to be president, while just 39 percent said Biden was mentally sharp enough for the presidency. By comparison, 56 v of poll respondents said Trump is too old for the office, while 54 percent said he was mentally sharp enough to handle the challenges of the presidency.

Jean-Pierre, asked about polls showing concern about Biden's age, said Biden has managed to mark some major legislative achievements and that he should be judged on his record, not his age.

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(Production: Paul Vieira)