Donald Trump gave an hourlong news conference Wednesday in which he recommitted to debating Vice President Kamala Harris.
As Mr Trump addressed reporters in a rambling conference at his Palm Beach, Florida, estate, ABC announced that he and Ms Harris have agreed to a September 10 presidential debate, setting up a widely anticipated face-off in the US presidential election run-up.
Mr Trump said he also wants to add two more debates that month - on September 4 and 25 - on Fox and NBC.
The Republican presidential nominee did not detail specific terms, such as whether there would be an audience, and it was not immediately clear whether his campaign had made a proposal to Harris' camp.
The Harris campaign did not immediately comment.
Mr Trump had previously suggested he might back out of the ABC debate, which was scheduled before Ms Harris, the US vice president, replaced President Joe Biden as the Democratic presidential candidate less than three weeks ago, upending the contest.
The news conference was Mr Trump's first public appearance since Ms Harris selected Minnesota Governor Tim Walz as her running mate on Tuesday.
Ms Harris and Mr Walz have headlined rallies in the battleground states of Pennsylvania, Michigan and Wisconsin this week, drawing tens of thousands of attendees in a fresh sign of how her late entry into the race has galvanised Democrats.
Her rapid rise has sent Mr Trump's team scrambling to recalibrate their strategy and messaging.
Opinion polls show Ms Harris has erased the lead Mr Trump had built over President Joe Biden, and Democrats have raked in hundreds of millions of dollars from voters and big donors in a matter of weeks.
Asked on Thursday how he has altered his approach to the new challenge from Ms Harris, Mr Trump insisted he has not done so.
In a question-and-answer session with reporters that stretched beyond an hour, Mr Trump moved from topic to topic, claiming Ms Harris and Mr Walz were weak candidates who were already dropping in the polls.
Despite that, he lamented that he isn't able to face Mr Biden in the election, suggesting that the president was a victim of an unconstitutional plot to dislodge him from atop the Democratic ticket.
Mr Biden dropped his faltering re-election bid under pressure from fellow Democrats worried about his chances of victory in the November 5 election after a poor debate performance against Mr Trump.
Mr Trump also mocked the size of Ms Harris' campaign crowds, even though they have matched his of late.
He falsely claimed the size of the crowd he addressed on January 6, 2021 - the day his supporters stormed the U.S. Capitol - was as large as those who packed the National Mall in Washington for Dr Martin Luther King's "I Have a Dream" speech in 1963.
"We actually had more people," Mr Trump said. "But I'm OK with it, because I liked Dr. Martin Luther King."
Mr Trump criticised Ms Harris for not doing a press interview since launching her campaign.
"She can't do an interview. She's barely competent," Mr Trump said, later again calling her "nasty," a go-to line that he often uses to disparage female critics.
The Harris campaign cancelled events on Thursday in North Carolina and on Friday in Georgia, where Tropical Storm Debby is bringing heavy rain and dangerous flooding.
The Democrats will head to Arizona and Nevada later this week, visiting two more swing states likely to play a key role in the November 5 election.
Mr Trump's running mate, Senator JD Vance of Ohio, also canceled campaign events in North Carolina on Thursday due to the storm. He has spent the last few days trailing Ms Harris and Mr Walz around the country - an unusual move intended to provide a "contrast," he told reporters on Wednesday.
