The move comes one day after the nonpartisan Commission on Presidential Debates announced the debate would be held virtually, following the president's diagnosis of and hospitalization for the novel coronavirus.
"On October 8, CPD announced that for the health and safety of all involved, the second presidential debate, scheduled for October 15 in Miami, would be conducted virtually," the CPD said in a statement, officially announcing the cancellation of the debate. "Subsequently, the campaigns of the two candidates who qualified for participation in the debate made a series of statements concerning their respective positions regarding their willingness to participate in a virtual debate on October 15, and each now has announced alternate plans for that date."
"It is now apparent there will be no debate on October 15, and the CPD will turn its attention to preparations for the final presidential debate scheduled for October 22," the CPD added.
Immediately after that announcement was made about a virtual debate Thursday morning, Trump said in an interview with Fox Business anchor Maria Bartiromo he would not "waste my time with a virtual debate" and was not going to participate.
The Trump campaign later Thursday said the president would participate if the debate -- as well as the third scheduled debate -- were pushed back a week. The Biden campaign shot down that idea, noting the dates had been decided in June.
With Trump refusing to participate to a virtual format, Biden agreed to participate in an ABC News town hall moderated by ABC News Chief Anchor George Stephanopoulos in Philadelphia on Oct. 15, the original date of the second debate, taking questions directly from voters.
Trump also scheduled his own town hall event for the night. He'll be taking part in an event aired on NBC Thursday night in Miami, sources familiar told ABC News.
Biden's reacted to the cancellation of the second presidential debate in a statement through a spokesperson, calling it "shameful" that Trump "ducked the only debate in which the voters get to ask questions."
"Vice President Biden looks forward to making his case to the American people about how to overcome this pandemic, restore American leadership and our alliances in the world, and bring the American people together," campaign spokesman Andrew Bates said. "It's shameful that Donald Trump ducked the only debate in which the voters get to ask the questions -- but it's no surprise. Everyone knows that Donald Trump likes to bully reporters, but obviously he doesn't have the guts to answer for his record to voters at the same time as Vice President Biden."
Trump 2020 communications director Tim Murtaugh slammed the "biased commission" for canceling the Oct 15 debate, saying "there's no medical reason to stop" it.
"There's nothing that says that President Trump and Joe Biden can't debate together without the overlords at the commission having a say in the matter," Murtaugh added. "We would be glad to debate one-on-one without the commission's interference."
Trump is also expected to host an event at the White House on Saturday, the first day his doctor cleared him to participate in "public engagements," and a rally in Sanford, Florida, on Monday.
Both candidates have agreed to participate in the next debate, moderated by Kristen Welker of NBC News, on Oct. 22.
ABC News' Justin Gomez and Drew Millhon contributed to this report.