WASHINGTON — President Donald Trump, under growing pressure to rescue an economy in free fall, said Monday that he may soon loosen federal guidelines for social distancing and encourage shuttered businesses to reopen — defying public health experts, who have warned that doing so risks accelerating the spread of the novel coronavirus or even allowing it to rebound.

"America will again and soon be open for business — very soon," Trump said at the daily White House news conference. "We cannot let the cure be worse than the problem itself."

As he has watched stock prices plummet and braces for an expected surge in unemployment, Trump has received urgent pleas from rattled business leaders, Republican lawmakers and conservative economists imploring him to remove some of the stringent social distancing guidelines that he put in place for a 15-day period ending March 30, according to several people with knowledge of the internal deliberations.

The various arguments, which are gaining traction across the political right, can be boiled down to this: No matter how many people may lose their lives to the coronavirus, many millions more stand to lose their jobs and face ruin if the economy does not reopen.

The consensus among experts — including infectious-disease expert Anthony Fauci and other senior officials on Trump's coronavirus task force — is that restaurants, bars, schools, offices and other gathering places should remain closed for many more weeks to mitigate the outbreak, the worst effects of which are yet to be felt in the United States.

But Trump has been chafing against that notion and impatient to get American life back to normal.

"If it were up to the doctors, they'd say let's keep it shut down, let's shut down the entire world … and let's keep it shut for a couple of years," Trump said Monday. "We can't do that."

Trump predicted that "we're going to be opening our country" in a shorter time frame than months. He announced that the administration was developing new protocols to allow local economies outside of what he called "hot spots" of the coronavirus spread to resume activity and would make a decision at the conclusion of the current 15-day period.

Trump drew parallels to the flu season, which he said was on pace to be responsible for the deaths of about 50,000 Americans, as well as to car crashes — comparisons that Fauci and other experts have dismissed as examples of false equivalency.

"You look at automobile accidents, which are far greater than any numbers we're talking about," Trump said. "That doesn't mean we're going to tell everybody no more driving of cars."

Trump's deliberations — detailed in interviews with more than 20 senior administration officials, outside advisers and other people briefed on the internal discussions, many of whom spoke on the condition of anonymity to share candid assessments — present to a nation already on edge about the pandemic a remarkable portrait of a president in limbo.

Inside the White House, tensions are growing over how quickly people can return to work. Trump's pending decision sets up a clash between the scientific experts advocating strict restrictions and the political and economic advisers who share and encourage the president's impatience.

In his public comments, Trump has conveyed uncertainty about how to protect the public's health while staving off economic calamity — and, especially, about the period of time during which Americans' lives will remain upended.

Trump tweeted his indecision at 11:50 p.m. Sunday, a message he reiterated to his followers midday Monday after news of his pending pivot was widely reported: "WE CANNOT LET THE CURE BE WORSE THAN THE PROBLEM ITSELF. AT THE END OF THE 15 DAY PERIOD, WE WILL MAKE A DECISION AS TO WHICH WAY WE WANT TO GO!"

Trump has cast himself as a "wartime president" but has publicly vacillated about the severity and length of restrictions. Last week, he said guidelines may be in place until July or August, but the messages he wrote or shared Monday on Twitter covered the gamut, from a video featuring Fauci explaining the benefits of "physical separation of people" to complaints from ordinary citizens that they were under "house arrest."

Democrats criticized Trump for his scattershot messaging.

"He's a notion-monger, just tossing out things that have no relationship to a well-coordinated science-based governmentwide response to this," House Speaker Nancy Pelosi, D-Calif., said.

Even with much of the country adopting social distancing measures, such as remaining six feet away from other people outside their household and working from home if possible, the number of coronavirus cases has surged as testing becomes more readily available to people experiencing symptoms.

More than 42,000 people in the United States have tested positive for covid-19, the disease the virus causes, and the death toll surpassed 500 on Monday, when more than 100 deaths were reported in a single day for the first time. The spread nationally is expected to dramatically increase in coming days as access to testing expands and results are processed.

Fauci, the National Institute of Allergy and Infectious Diseases director, and other leading public health experts have told administration officials that prematurely scaling back social distancing could not only hamper mitigation efforts, but also overwhelm hospitals.

Still, Trump is fixated on the economy — alarmed by the effects of the coronavirus so far and concerned about the impact of long-term contraction and surging unemployment on his reelection chances in November, according to people familiar with his discussions.

There is a growing fear inside the administration that an effective freeze on an array of major sectors of the economy for an indefinite period could be economically unsustainable no matter what stimulus package Congress passes or what monetary levers the Federal Reserve pulls.

Though restrictions on restaurants and other business have been set by state governments, the president could influence practices if he changed the federal government's guidelines about social distancing and business closures.

The push for Trump to do so has come from broad swaths of his political coalition, from prominent economists and media figures to key lawmakers in the Senate and the House.

The Wall Street Journal's influential editorial board published an editorial late last week calling on the administration, as well as governors, to rethink their coronavirus mitigation strategies. "No society can safeguard public health for long at the cost of its overall economic health," the board wrote.

Conservative economists Stephen Moore and Art Laffer have been lobbying the White House for more than a week to strongly consider scaling back the recommendation that restaurants, stores and other gathering spots be closed, although exactly what that would entail remains unclear.

Financial titans, including former Goldman Sachs chief executive Lloyd Blankfein, and conservative media figures also have embraced the idea.

"In one week we need to be heading back to work, school, stores, restaurants and churches with new protocols in place," Laura Ingraham, a conservative commentator whose show on Fox News Channel the president is known to watch regularly, tweeted Monday.

Conservatives close to Trump and numerous administration officials have been circulating an article by Richard Epstein of the Hoover Institution, titled "Coronavirus Perspective," that plays down the extent of the spread and the threat. The article, published last week, had predicted that deaths would peak at 500, the milestone surpassed Monday.

Trump has been canvassing his advisers, Republican lawmakers and other allies about what his course of action should be, and in his deliberations, a natural tension has emerged between the advice of Fauci and other medical experts and that of business leaders, such as those in the hospitality industry, which included Trump before he entered politics.

One senior administration official said there is a widespread understanding among government officials about the need to reopen the economy but that proposals have not yet been presented to Trump. Officials have considered options, including allowing people to go back to work if they are able to avoid public transportation or to return to their jobs if they are not in areas with high infection rates.

The coronavirus task force led by Vice President Mike Pence has sought to take the economic and health ramifications of the outbreak seriously and worked to balance the two priorities, officials have said. Treasury Secretary Steven Mnuchin, National Economic Council Director Larry Kudlow and officials from the Office of Management and Budget are seen internally as conduits for the business community and have been pushing to get the economy back on track as quickly as possible, according to people familiar with the matter.

"The president is right. The cure can't be worse than the disease," Kudlow said Monday on Fox News Channel. "And we're going to have to make some difficult trade-offs."

One option under consideration is a gradual scaling back of current restrictions in which people younger than 40 who are healthy go back to work on a certain date, followed by people ages 40 to 50, according to one person briefed on the discussions.

Describing the overall dynamic, Moore said in an interview, "You have a classic case of the public health people saying, ‘We have to keep everyone sequestered for as long as this takes without any regard to the economic cost.’ The economics team is saying, ‘If this lasts seven to 10 weeks, there won’t be much of an economy to save.’ "

Moore added, "I'm not in any way disparaging the public health people. They are vital to this process. But you can't have a policy that says we're going to save every human life at any cost, no matter how many trillions of dollars you're talking about."

There is dissent within the Republican Party, however, including from some close allies of the president.

"It would be a major mistake to suggest any change of course when it comes to containment," Sen. Lindsey Graham, R-S.C., said in an interview. "I just spoke with Dr. Fauci — he believes that, if anything, we should be more aggressive and do more … You can't have a functioning economy if you have hospitals overflowing."

While Trump has focused on the 15-day timeline, health experts said that is not expected to be enough time to defeat the virus's spread. Cases in the United States are rapidly increasing and have not yet reached their peak, but hospitals are experiencing severe shortages of protective equipment and ventilators to treat the increasing numbers of patients. Because of the delays expanding testing capabilities, the country still does not have comprehensive data about the spread of the virus and its mortality rate.

Public health experts have strongly warned against any loosening of social distancing measures. Marc Lipsitch, an epidemiology professor at Harvard University's T.H. Chan School of Public Health and director of Harvard's Center for Communicable Disease Dynamics, said, "Now is the time to tighten restrictions on contacts that could transmit the virus, not loosen them."

"If we let up now, we can be virtually certain that health care will be overwhelmed in many if not all parts of the country," Lipsitch said. "This is the view of every well-informed infectious epidemiologist I know of."

Yasmeen Abutaleb, John Wagner and Erica Werner contributed to this article.