Trump had originally signaled a desire to return to business as usual by Easter Sunday — April 12—even as the U.S. became the new global epicenter of the outbreak, but reversed course Sunday during the White House coronavirus task force press briefing.

"Nothing would be worse than declaring victory before the victory is won," Trump said, as The Guardian reported. "That would be the greatest loss of all. Therefore the next two weeks, and during this period it's very important that everyone follow the guidelines. The better you do, the faster this whole nightmare will end."

The extended measures advise Americans to avoid non-essential travel, going to work, restaurants or bars and gathering in groups of 10 or more, according to The New York Times. They were set to expire Monday after a two-week period but will now continue at least until the end of April.

Trump's reversal comes two days after a group of more than 800,000 doctors wrote a letter to the president urging him not to relax social distancing guidelines by Easter. It also comes based on the advice of his own top health experts: Dr. Anthony Fauci of the National Institute of Allergy and Infectious Diseases and Dr. Deborah Birx, the response coordinator of the White House coronavirus task force.

"Dr. Birx and I spent a considerable amount of time going over all the data, why we felt this was a best choice for us, and the president accepted it," Fauci told The New York Times.

Fauci and Birx's advice was based on models showing that, even with social distancing, as many as 200,000 Americans could die of COVID-19 and millions could become infected, NPR reported. Without social distancing, around 2.2 million Americans could die.

"The idea that we may have these many cases played a role in our decision in trying to make sure that we don't do something prematurely and pull back when we should be pushing," Fauci told The New York Times.

Trump's reversal breaks with past precedent. He has downplayed his own agencies' warnings over the course of the coronavirus outbreak and has contradicted his own scientists in the past, especially on the issue of the climate crisis. He dismissed his government's own National Climate Assessment with the words, "I don't believe it."

When asked about his earlier Easter goal, Trump refused to say it was a mistake.

"It was just an aspiration," Trump said, according to NPR.

Trump on Sunday shifted his hopes for recovery till early June.

"We can expect that by June 1st, we will be well on our way to recovery, we think by June 1st. A lot of great things will be happening," he said, according to CNN.

According to Monday morning figures from Johns Hopkins University School of Medicine, there have been 724,945 confirmed cases of coronavirus in the world and 143,055 in the U.S. Worldwide, more than 34,000 have died. The U.S. death toll doubled over the weekend from slightly more than 1,000 on Thursday to 2,114 on Saturday, The Independent reported.