US President Donald Trump is itching to get back on the campaign trail after being sidelined by a COVID-19 infection but is unlikely to hold any in-person events until at least Monday, aides say.

Uncertainty remains about whether Mr Trump, who was diagnosed with COVID last week, is still contagious.

White House spokeswoman Kayleigh McEnany said the president was ready to go as soon as he got approval from his doctor, telling Fox News: “He wants to talk to the American people, and he wants to be out there”.

“There are medical tests underway that will ensure that when the president is back out he will not be able to transmit the virus,” Ms McEnany said, adding Dr Conley would lay out the details later.

“He won’t be out there if he can transmit the virus.”

Eric Trump hosts a Make America Great Again event and meets local supporters on while the president is in isolation. Photo: Getty

It comes as Democrat House Speaker Nancy Pelosi said the president appeared to be “in an altered state right now” and queried a potential “impairment of judgment”.

Ms Pelosi has been raising questions about Mr Trump’s mental fitness since his COVID-19 diagnosis and demanding more transparency about his health.

She unveiled legislation that would allow Congress to intervene to remove a president but insisted it was not about Mr Trump.

The bill would set up a commission to assess a president’s ability to lead the country and ensure a continuity of government.

Ms Pelosi said it was inspired by the need for greater congressional oversight of the White House.

“This is not about President Donald Trump – he will face the judgment of the voters,” Ms Pelosi said at a press conference at the Capitol on Friday.

Nancy Pelosi has raised questions about Donald Trump’s judgement during his brush with COVID.

The president’s opponents have discussed invoking the 25th Amendment for some time but are raising it now, so close to election day, as the campaigns are fast turning into a referendum on Mr Trump’s handling of the coronavirus pandemic.

The legislation that would create a commission as outlined under the 25th Amendment, which was passed by Congress and ratified in 1967 as a way to ensure a continuity of power in the aftermath of President John F Kennedy’s assassination.

It says the vice president and a majority of principal officers of the executive departments “or of such other body as Congress” may by law provide a declaration to Congress that the president “is unable to discharge the powers and duties of his office”.

At that point, the vice president would immediately assume the powers of acting president.

Just weeks before the November 3 election, with no hopes of the bill becoming law, the roll-out was quickly dismissed as a stunt by Mr Trump’s team and top allies.

“It’s an absurd proposal,” said Ms McEnany on Fox.

“Absolutely absurd,” said Senate Majority Leader McConnell during an appearance in Shepherdsville, Kentucky.

Congress is not in legislative session and so any serious consideration of the measure, let alone votes in the House or Senate, is unlikely.