President Trump has canceled a three-day trip to Nevada and Colorado, including a speech to the Republican Jewish Coalition in Las Vegas, due to “an abundance of caution” over the coronavirus outbreak, the White House said late Wednesday.

Trump’s campaign quickly followed suit and called off a “Catholics for Trump” kickoff rally scheduled in Milwaukee next week, which had been publicly announced just a day earlier.

The president’s long-planned trip, which was set to begin Thursday, also included a private dinner with Republican donors in Las Vegas and a fundraiser with Sen. Cory Gardner (R) in Colorado. Organizers of the RJC conference, which also has now been postponed, and Las Vegas city officials had said earlier Wednesday that the event was still a go and that Trump and former U.N. ambassador Nikki Haley were expected to attend.

White House press secretary Stephanie Grisham made the announcement in an email to reporters, shortly after Trump finished prime-time remarks at the White House, during which he said the United States would halt all travel from Europe for 30 days to try to slow the spread of the illness.

Big cities are moving to shut down large public gatherings to protect against the coronavirus, including Washington and San Francisco, which have called for the cancellations of any events with more than 1,000 people. The RJC had expected up to 2,000 attendees, but about a quarter already had dropped out due to fears of the virus, organizers said, and one speaker from Israel had canceled because of visa restrictions in that country.

In addition to the conference speech, Trump and Secretary of State Mike Pompeo were planning to speak at a preconference dinner with prominent Jewish Republicans on Thursday evening.

There have been five confirmed cases of the virus in Clark County, where Las Vegas is located, according to the Southern Nevada Health District.

Earlier in the day, city officials had expressed confidence that the RJC conference would be safe. Michele Fiore, a Las Vegas City Council member and mayor pro tem who had planned to attend the conference, said in an interview: “I’m excited our president is traveling around and living his best presidential life the way he is supposed to — he’s meeting folks and not letting fear take over. We really believe it’s safe enough. . . . We are encouraging all our conventions and meetings to go on no matter how many thousands of people.”

She could not be immediately reached for comment after the president’s trip and the conference were canceled.

Trump has sought to project confidence and maintain a business-as-usual routine in hopes of reassuring the public, even as other administration officials have warned that the virus will continue to spread and recommended that the public adopt social distancing practices. Seattle, where the most confirmed cases in the United States have been found, has shut down public schools for two weeks. Major sports leagues are planning games with no spectators.

But Trump’s 2020 campaign on Tuesday had announced it would hold a “Catholics for Trump” kickoff event in Milwaukee on March 19, at a facility that can hold more than 3,000. The move came on the same day that Democratic presidential candidates Joe Biden and Sen. Bernie Sanders (I-Vt.) canceled campaign rallies over coronavirus concerns.

Tim Murtaugh, the campaign’s communications director, said in a tweet late Wednesday that the event will be rescheduled.

Asked whether he thought it would be safe to go forward with the event in Milwaukee, Sen. Ron Johnson (R-Wis.) said before it was canceled: “It’s hard to answer that question right now until we literally have test kits deployed, the lab technicians trained and we get a better sense of exactly what’s happening. It may not be. It may be okay. We do need more information.”

Public health experts have called on extreme measures to slow the virus, but for Trump the decision about whether to continue with a robust public schedule is laced with concerns over not wanting to instill greater fear in the public. On top of that, with financial markets plummeting more than 20 percent from their all-time highs, the president is under pressure from executives in the tourism and travel industry who worry that widespread cancellations will wreak further damage to the economy.

“Some of the international conferences have been canceled, but we’re still going forward with the number of conventions,” Rep. Dina Titus (D-Nev.), whose district includes Las Vegas, said before the RJC conference being postponed. She pointed to the NFL Draft, which is scheduled for late April. “We’re trying to be smart but not be panicked.”

The risks of large-scale events came into sharp relief last week, when an attendee at the Conservative Political Action Conference late last month at Maryland’s National Harbor was later diagnosed with the coronavirus. Trump spoke at the event, and several Republican lawmakers who were there put themselves into self-quarantine, although none have been found to test positive.

Trump had interacted with two of those lawmakers, shaking hands with Rep. Douglas A. Collins (R-Ga.) in Atlanta last week and riding with Rep. Matt Gaetz (R-Fla.) on Air Force One on Monday. Trump has said he has not been tested for the virus, because doctors have said it is not necessary.

In a coronavirus meeting at the White House with banking executives Wednesday, Trump noted that China and South Korea had made headway in slowing the number of new cases and projected a hopeful note that the United States will be “getting back involved in that part of the world.” But he also noted that several European nations, including Italy and France, have seen a rapid increase and are in “tough shape.”

The RJC is a small but politically powerful organization representing conservative Jewish Republicans, a constituency Trump has courted. He addressed the group last year.

Neither the White House nor the casino and hotel industry in Las Vegas had put any pressure on the RJC to go ahead with the conference, said RJC Director Matt Brooks.

Thursday on Twitter, Brooks denied an assertion from conservative writer and pundit William Kristol that RJC backer Sheldon Adelson, a hotel magnate and GOP donor, wanted the event to go on.

“Falsehoods and fabrications,” Brooks wrote.

Kristol had called the decision to hold the event “totally irresponsible” and suggested the RJC was “scared to cross” Adelson.

“I assume Trump’s proposed bailout will include money for Sheldon’s hotels,” Kristol wrote.

The meeting was to be held at the Venetian hotel, in one of the largest auditoriums on the Las Vegas Strip. The RJC organizers had said they planned to pass out individual supplies of hand sanitizer and ask each participant to refrain from handshakes, hugs and kisses.

Sen. Jacky Rosen (D-Nev.) said she expects the White House to continue to assess the risks as Trump seeks to maintain his public schedule.

“He comes in front of a lot of people,” she said. “I think it’s important that he stay safe and healthy.”