President Trump delivered a rally-like address to the Republican National Convention on Monday in a surprise appearance in Charlotte, N.C., after he was officially nominated for the 2020 GOP ticket.

Trump’s remarks, which lasted about an hour, touched on a variety of topics but repeatedly returned to the pandemic and mail-in voting, arguing that expanding access to mail-in ballots could invite massive fraud in the election — a claim experts say is not substantiated.

He spoke optimistically about the prospect of economic recovery — pledging to create 10 million jobs in 10 months if he is reelected — and warned that his opponent, Democratic nominee Joe Biden, would raise taxes and increase regulations, making it “impossible to build a highway.”

Trump also asserted that the country is “doing very, very well” against the coronavirus, which has killed more than 176,000 people in America and caused millions to lose their jobs.

Trump delivered his surprise speech minutes after he was formally selected as the 2020 Republican nominee for president to take on Biden, who is currently leading him in national and battleground polling. The Democratic National Convention last week featured biting criticism of Trump’s response to the coronavirus pandemic as well as his character. A CNN survey released last week found that 58 percent of Americans disapprove of Trump’s response to the virus.

Trump claimed that decisions to restrict business operations and expand access to mail-in voting were driven not by the pandemic but by politics.

"What they’re doing is using COVID to steal an election," Trump said. "They’re using COVID to defraud the American people, all of our people, of a fair and free election. We can’t do that."

Trump drifted from topic to topic in his remarks, which were delivered before an audience in Charlotte. Trump appeared to enjoy the setting and occasionally riffed off remarks and cheers from the crowd, suggesting at one point that attendees chant "12 more years" and not four if they really wanted to drive his opponents crazy.

He switched between trumpeting his administration’s work and attacking his political opponents, mimicking his style at his campaign rallies that have largely been sidelined due to the pandemic.

Trump rattled off a number of accomplishments including efforts to secure the border, bring back manufacturing jobs, build the wall at the southern border, defeat the Islamic State caliphate and lower drug prices. Trump at times overstated his administration’s efforts, including saying that he was close to appointing 300 judges to the federal bench. The Senate confirmed Trump’s 200th judicial appointment at the end of June.

“We’ve accomplished more than just about any administration in the history of our country,” Trump asserted.

Both Trump and Vice President Pence made surprise appearances at the convention after they were officially nominated by GOP delegates, as the Trump campaign seeks to drive momentum with the weeklong convention events.

The Trump campaign has been teasing surprises ahead of the convention, which will stretch over four days and began Monday. The president is expected to appear in some capacity each night of the convention, including meeting with front-line workers on Monday evening.

The Republican National Convention events, including Trump’s acceptance speech on Thursday, were originally supposed to take place in Charlotte, but the president moved most of them to Jacksonville, Fla., over a dispute with the North Carolina Gov. Roy Cooper (D) about coronavirus limits on the events.

Trump was forced to scrap the Jacksonville portion of the convention in July, however, amid rising coronavirus cases in the Sunshine State. The president will deliver his acceptance speech from the White House, suggesting in his remarks Monday that he would focus in part on the administration’s response to the coronavirus during the address.

Still, Trump took the opportunity to rip Cooper during his remarks Monday, claiming he was in a “total shutdown mood” and suggesting that Democrats were keeping strict restrictions in place to prevent the spread of the virus to hurt the economy and therefore his reelection prospects.

Trump sought to draw a contrast with Biden with his visit to the convention, which was considerably scaled down due to the coronavirus. Only 336 delegates were present for Monday’s GOP nominating business.

Trump told the delegates he felt an “obligation” to visit North Carolina, a key battleground state that the president won by about 3 percentage points against Democrat Hillary Clinton in 2016.

“I felt an obligation to come to North Carolina. It’s been a place that’s been very good to me,” Trump said, before dinging Biden for not traveling to Wisconsin, the state that was supposed to be the site of the Democratic convention before organizers moved it online for safety reasons because of COVID-19. Trump and Pence each traveled to Wisconsin to campaign last week.

Aside from the nominating proceedings, the Republican convention will be largely virtual, with speakers delivering remarks from sites in Washington, D.C., and across the country. Trump’s address at the White House is still expected to have an audience of some sort.