House Speaker Nancy Pelosi is questioning President Donald Trump’s fitness to serve, announcing legislation that would create a commission to allow Congress to intervene under the US Constitution’s 25th Amendment and remove the president from executive duties.

Just weeks before the November 3 election, Ms Pelosi said Mr Trump needed to disclose more about his health after his Covid-19 diagnosis.

She noted Mr Trump’s “strange tweet” halting talks on a new coronavirus aid package — he subsequently tried to reverse course — and said Americans needed to know when, exactly, he first contracted Covid as others in the White House became infected.

On Friday, she plans to roll out the legislation that would launch the commission for review.

“The public needs to know the health condition of the president,” Ms Pelosi said, later invoking the 25th Amendment, which allows a president’s cabinet or Congress to intervene when a president is unable to conduct the duties of the office.

Mr Trump responded swiftly via Twitter.

“Crazy Nancy is the one who should be under observation. They don’t call her Crazy for nothing!” the president said.

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.

More than 211,000 Americans have died and millions more have been infected by the virus that shows no signs of abating heading into what public health experts warn will be a difficult flu season and winter.

Mr Trump says he “feels great” after his stay in hospital and is back at work in the White House. But his doctors have given mixed signals about his diagnosis and treatment. Mr Trump plans to resume campaigning soon.

Congress is not in legislative session, and so any serious consideration of the measure, let alone votes in the House or Senate, is unlikely. But the bill serves as a political tool to stoke questions about Mr Trump’s health as his own White House is hit by an outbreak infecting top aides, staff and visitors, including senators.

In a stunning admission, Senate Majority Leader Mitch McConnell said Thursday that he had stopped going to the White House two months ago because he disagreed with its coronavirus protocols. His last visit was August 6.

“My impression was their approach to how to handle this was different from mine and what I insisted we do in the Senate, which is to wear a mask and practice social distancing,” Mr McConnell said at a campaign stop in northern Kentucky for his own re-election.

On Friday, Ms Pelosi along with Democratic Representative Jamie Raskin, a constitutional law professor, plan to roll out 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.

Mr Trump abruptly halted talks this week on the new Covid aid package, sending the economy reeling, his GOP allies scrambling and leaving millions of Americans without additional support. Then he immediately reversed course and tried to kickstart talks.

It all came in a head-spinning series of tweets and comments days after he returned to the White House after his admission to hospital with Covid-19.

First, Mr Trump told the Republican leaders in Congress on Tuesday to quit negotiating on an aid package. By Wednesday he was trying to bring everyone back to the table for his priority items — including 1,200-dollar (£926) stimulus checks for almost all adult Americans.

Ms Pelosi said on Thursday that Democrats were “still at the table” and her office resumed conversations with top negotiator, Treasury Secretary Steven Mnuchin.