President Donald Trump has vowed not to participate in next week’s debate with Democratic nominee Joe Biden after organisers announced it will take place virtually because of the president’s diagnosis of Covid-19.

“I’m not going to do a virtual debate” with Mr Biden, Mr Trump told Fox News, moments after the nonpartisan Commission on Presidential Debates announced the changes.

The shake-up comes a week before Mr Trump and Mr Biden were set to square off for the second presidential debate in Miami.

Mr Biden’s campaign insisted its candidate was ready to move forward, but the future of the event is now in serious doubt.

“Vice President Biden looks forward to speaking directly to the American people,” deputy Biden campaign manager Kate Bedingfield said in a statement.

The Commission on Presidential Debates made the decision unilaterally, citing the need “to protect the health and safety of all involved with the second presidential debate”.

When Republican Mike Pence and Democrat Kamala Harris squared off for their only vice presidential debate in Salt Lake City on Wednesday night, they shared a stage but were separated by plexiglass to prevent the spread of the virus.

Mr Trump’s campaign said the president would do a rally instead of the debate.

“For the swamp creatures at the Presidential Debate Commission to now rush to Joe Biden’s defence by unilaterally cancelling an in-person debate is pathetic,” Bill Stepien, Trump campaign manager said in a statement.

“The safety of all involved can easily be achieved without cancelling a chance for voters to see both candidates go head to head. We’ll pass on this sad excuse to bail out Joe Biden and do a rally instead.”

US Election
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Trump was admitted to hospital for three days but is now back at the White House recovering.

He has vowed to return to the campaign trail soon.

Still, the commission’s move is yet another indication that the presidential election is being dominated by the virus.

“I don’t want to do a virtual debate because (a) virtual debate is a joke. There’s no reason. I’m in great shape,” Mr Trump said.

Boarding a flight to campaign in Arizona on Thursday, Mr Biden said it’d be “irresponsible” for him to comment.

“We don’t know what the president’s going to do. He changes his mind every second” and could ultimately end up debating anyway,” Mr Biden said.

Deputy Biden campaign manager Kate Bedingfield said in a statement: “Vice President Biden looks forward to speaking directly to the American people.”

A Biden aide said it would be up to the debate organisers to decide whether the former vice president would get a 90-minute broadcast to himself.

Aides did not immediately say what the campaign’s preference might be.

Asked about participating by himself, Mr Biden responded, “We don’t know enough to know right now.”

Mr Biden said earlier in the week that he was “looking forward to being able to debate him” but added “we’re going to have to follow very strict guidelines”.

He said he and Mr Trump “shouldn’t have a debate” as long as the president remains Covid-19 positive.

The Commission on Presidential Debates announced early on Thursday the candidates would “participate from separate remote locations” while the participants and moderator remain in Miami, it said.

Moments later, Mr Trump vowed to skip the event entirely.

Mr Trump was diagnosed with coronavirus a week ago, but in a Tuesday tweet said he looked forward to debating Biden a second time, “It will be great!” he tweeted.

He fell ill with the virus last Thursday, just 48 hours after debating Mr Biden in person for the first time in Cleveland.

While the two candidates remained a dozen feet apart during the debate, Mr Trump’s infection sparked health concerns for Mr Biden and sent him to undergo multiple Covid-19 tests before returning to the campaign trail.

Mr Trump was discharged from Walter Reed National Military Medical Centre on Monday.

According to the Centres for Disease Control and Prevention, those with mild to moderate symptoms of Covid-19 can be contagious for as many as — and should isolate for at least — 10 days.

It is not the first debate in which the candidates are not in the same room.

In 1960, the third presidential debate between Richard Nixon and John F Kennedy was broadcast with the two candidates on opposite coasts.