U.S. President Donald Trump confirmed on Tuesday that he's taking part in the second presidential debate against rival Joe Biden as planned. 

"I am looking forward to the debate on the evening of Thursday, October 15th in Miami. It will be great!" he tweeted on Tuesday. In another tweet, Trump said "FEELING GREAT!"

Trump returned to the White House on Monday after departing from Walter Reed National Military Medical Center, where he spent three nights being treated for the novel coronavirus.

His campaign also confirmed the plan on Tuesday, despite uncertainty around how the president will recover from COVID-19.

"The president intends to participate in the debate in person," the campaign's communications director, Tim Murtaugh, said in a statement to The Hill.

Trump campaign: President plans to take part in next debate in person

Biden: Debate should not take place if Trump still has COVID-19

It's not yet clear if the president will be healthy enough to attend the debate, or whether he would be exposing other attendees to a contagious virus that has killed roughly 210,000 people in the U.S. to date.

On Tuesday, Democratic presidential candidate Joe Biden said he and Trump should not have their scheduled debate if Trump still had the coronavirus infection at that time.

"If he still has COVID we shouldn't have a debate," Biden told reporters traveling with him.

Tump also said on Tuesday that he has asked his administration's negotiators to withdraw from COVID-19 relief talks with Democrats until after the presidential election in November, which Biden accused  Trump of having "turned his back" on Americans after the president abruptly halted the COVID-19 relief plan negotiations.

"He turned his back on every single worker whose job hasn't come back yet.... He turned his back on families struggling to pay rent, put food on their table, and take care of their kids," Biden said.

Read more:

Biden to take part in second debate given certain conditions: campaign aide

Trump ends COVID-19 relief talks with Democrats until after election

Meanwhile, Stephen Miller, senior advisor to Trump, has tested positive for COVID-19, the White House official said on Tuesday.

Trump first revealed that he tested positive for COVID-19 early last Friday morning, and he has had symptoms since at least then. But the White House has refused to say when Trump last tested negative or fill in the timeline around his diagnosis.

The Centers for Disease Control and Prevention (CDC) guidelines state that adults with mild to moderate COVID-19 can be around others 10 days after symptoms first appeared so long as they have gone 24 hours without a fever and other symptoms are improving.

The debate is scheduled to take place on October 15, which would be 13 days from when Trump first revealed his positive diagnosis.

The two rivals clashed in a controversial and chaotic first debate on September 29 prompting the CPD, the group that manages U.S. presidential election debates, pledged to take steps to ensure a more orderly discussion.

So far, more than three million people have already voted and Joe Biden has extended his lead over Donald Trump in the national polls after seven remarkable days in the race for the White House.

2020 in 120 seconds: Trump positive, debate negative, Biden leads

(With input from agencies)