U.S. President Joe Biden is healthy, his doctor said Wednesday, following the 81-year-old's annual physical examination at a military hospital conducted at a time when many voters are concerned about his fitness to serve a second term in the White House.

"The president feels well and this year's physical identified no new concerns," Biden's physician, Kevin O'Connor, wrote in a six-page memo. "He continues to be fit for duty and fully executes all of his responsibilities without any exemptions or accommodations."

The document sent to the White House after Biden spent more than two and a half hours at Walter Reed National Military Medical Center near Washington for the checkup also characterized him as a "healthy, active, robust 81-year-old male."

U.S. President Joe Biden is pictured at the White House in Washington on Feb 28, 2024. (Getty/Kyodo)

Biden, the oldest president in U.S. history, joked later at an event on fighting crime that a team of doctors "think I look too young," assuring reporters "everything is great" regarding his health.

Biden would be 86 at the end of a second four-year term, if he wins the 2024 presidential election. The Democratic president has repeatedly said he is in good shape as he prepares for a likely rematch with his predecessor Donald Trump in November.

But public concern about Biden's age grew earlier this month after a special counsel report on his handling of classified documents described him as a man with "a poor memory."

The routine exam's findings came a day after Trump handily won Michigan's Republican presidential primary, defeating remaining rival Nikki Haley in the party's nomination race for the election, extending his undefeated streak to six contests.

Biden and Trump, 77, have accused each other of suffering from mental decline. Haley, meanwhile, said the two men are both too old to make critical decisions for the United States.

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