Democratic White House candidate Kamala Harris is in "excellent health" and fit for the presidency, according to a medical report published by the White House Saturday, as she challenged rival Donald Trump to publish his own health records.

"Vice President Harris remains in excellent health," her physician Joshua Simmons said in the report, adding that she "possesses the physical and mental resiliency required to successfully execute the duties of the presidency."

Speaking to reporters on Saturday ahead of a trip to North Carolina, Harris called Trump's unwillingness to publish his records "a further example of his lack of transparency."

"It's obvious that his team at least, does not want the American people to see everything about who he is... and whether or not he is actually fit to do the job of being president of the United States," she said.

But as Harris ramped up pressure for details on the physical health and mental acuity of the 78-year-old Trump, the former president's campaign pushed back.

The Republican candidate is also "in perfect and excellent health to be Commander in Chief," it said in a statement, and charged that Harris lacked his strength to lead the country.

Harris's most recent physical exam, conducted in April, was "unremarkable," according to Simmons.

In the detailed report, her physician noted that Harris suffers from seasonal allergies and hives, which are managed by non-prescription as well as prescription medications. The vice president is also slightly nearsighted and wears contact lenses, the report said.

Trump became the oldest presidential nominee from a major political party in US history after 81-year-old President Joe Biden withdrew from the White House race in July. Harris is 59.

Biden passed the torch to Harris after a disastrous debate against Trump raised concerns in the Democratic Party about his own mental sharpness.

But Trump's age has not appeared to be a deal-breaker for voters, as polls show a knife-edge battle with Harris in the November 5 presidential election.

Harris's campaign drew attention to a recent series of articles in The New York Times that raised concerns about Trump's failure to disclose basic information about his health.

The newspaper has also published an analysis of Trump's language showing that his speeches are increasingly long and "confused," and include vulgarities — a trend seen by experts as a possible sign of cognitive decline.