Donald Trump on Saturday rejected a second debate against Kamala Harris before the November 5 election, saying it was "too late" with early voting already underway in some states.
Earlier in the day, Harris's campaign said she had accepted an invitation from broadcaster CNN to participate in a debate on October 23. It would have been the candidates' second debate, after a September 10 encounter that most pundits said she had won.
"The American people deserve another opportunity to see Vice President Kamala Harris and Donald Trump debate before they cast their ballots," her campaign chair Jen O'Malley Dillon said in a statement.
"I hope (Trump) will join me," Harris posted on X.
Trump claimed during a campaign rally in the battleground state of North Carolina that he would like to debate -- calling it "good entertainment value" -- but the start of early voting in some states had taken the air out of the idea.
"It's just too late, voting has already started," he said.
He added, to a large and enthusiastic crowd of supporters, that while CNN had been "very fair" when he debated President Joe Biden in June, "they won't be fair again."
Vice President Harris replaced her boss at the top of the Democratic ticket after the 81-year-old Biden's disastrous performance against Trump.
His exit from the race left Trump, 78, now the oldest ever presidential nominee, against a much younger Harris, 59.
- Voting underway -
Saturday's announcement came as some states have already begun early voting in what is an agonizingly close race.
The result is expected to hinge on seven battleground states, including North Carolina.
Trump addressed the crowd in the port city of Wilmington from behind bulletproof glass, following an apparent second assassination attempt against him.
A gunman was discovered on his golf course in Florida last Sunday, with security agents foiling any plan to harm the former president.
In July, Trump was struck on the ear by a bullet at a rally in Butler, Pennsylvania, after a gunman opened fire from a nearby rooftop. The US Secret Service -- tasked with protecting the candidate -- on Friday admitted to "deficiencies" and "complacency" in the shocking security breach.
- Anti-immigrant rhetoric -
Trump won North Carolina in the 2020 election against Biden.
But Harris is aiming to flip the southeastern state for Democrats, on the strength of her support from African Americans and young voters.
Trump's speech on Saturday reinforced the hardline anti-immigrant rhetoric that has become a centerpiece of his campaign, falsely claiming migrants were "attacking villages and cities all throughout the Midwest."
He also promised the crowd that the United States would "reach Mars before the end of my term."
The former president was facing a new challenge in North Carolina after a bombshell report on Thursday revealed that Mark Robinson, the Republican candidate for governor whom Trump has endorsed, had called himself a "Black Nazi" and made other incendiary comments on a porn website message board more than a decade ago.
Robinson has denounced the CNN report as "salacious tabloid lies."
The presidential race remains neck-and-neck and every vote will count in the election, whose result Trump has once again refused to say he will accept if he loses.
Trump faces criminal charges for allegedly trying to overturn the 2020 result, after which his supporters violently stormed the US Capitol on January 6, 2021.