NEW YORK — President Trump on Sunday said he would approve the construction of four emergency hospital sites in and around New York City, heeding calls for urgent federal help as the Empire State shut down all nonessential businesses from Brooklyn to Buffalo in a bid to keep the number of coronavirus patients from spiraling out of control.

Nervous New Yorkers braced for their strange lives during the pandemic to get even stranger, with little more than the basic necessities available. New York is one of a handful of states to order a sweeping shutdown.

Responding to a public demand from New York Gov. Andrew M. Cuomo (D), Trump said he would authorize federal action on four temporary hospital sites, with 250 beds each to start. Trump said he has ordered the Federal Emergency Management Agency to ship mobile hospital centers to New York, as well as California and the state of Washington.

Earlier in the day, Cuomo said the state is doing everything it can to get necessary supplies and hospital beds, but the federal government has powers he does not, and he called on the White House to act quickly.

“Get the Army Corps of Engineers moving. Get FEMA moving. Let’s get those buildings up,” Cuomo said in a Sunday news conference. “Time matters. Minutes count. And this is literally a matter of life and death. We get the facilities up, we get the supplies, we will save lives. If we don’t, we will lose lives.”

Cuomo wants temporary hospitals at locations in Long Island, Westchester and Manhattan’s Javits Center, a giant convention hall.

“From my point of view, construction could start tomorrow,” he said. “There is no red tape on the side of New York.”

New York wants new hospital capacity urgently, because the rapid growth of cases suggest the state may need 110,000 beds. It currently has only about 53,000.

As of Sunday, more than 15,000 New Yorkers had tested positive for the novel coronavirus, and about 2,000 of them have required hospitalization. Of those confirmed cases, nearly 11,000 were in New York City, where nearly 1,800 are hospitalized.

Cuomo also wants the president to use the Defense Production Act to “take over that function of contracting and supplying all of the supplies we need.”

The problem, Cuomo said, is the demand for masks and other gear is so high, states and other government agencies are bidding up the prices to nearly 10 times their normal cost. If the federal government stepped in, that would end the bidding wars and create some order in the marketplace.

“Price gouging is a tremendous problem and it’s only getting worse,” Cuomo said. “There are masks that we were paying 85 cents for, we’re now paying seven dollars. Why? Because I’m competing against every other state, and in some cases, against other countries around the world.” He added that a similar difficulty exists in the market for ventilators to treat the most ill coronavirus patients.

“This is just an impossible situation to manage. If we don’t get the equipment, we can lose lives that we can otherwise save if we had the right equipment,” said the governor, who has already tried to convince area garment manufacturers to retool their production lines to make masks.

To try to stave off the spread of coronavirus, New York is one of a handful of states that have taken the drastic step of ordering all nonessential business to shut down. The order was to take effect at 8 p.m. Sunday. Some types of commerce, such as medical care and supplies, food production and distribution, and paper supplies are exempt from the order as essential activities. Businesses may be fined if they violate the governor’s order, but there are currently no such fines for individuals. People are advised to stay inside as much as possible, but officials have also encouraged solitary exercise, such as running or hiking, as long as people stay a safe distance from each other.

As he has done repeatedly in recent days, Cuomo complained at length about the number of people, particularly young people, who were ignoring the orders and advice to keep their distance from each other, and playing basketball in public parks or otherwise hanging out in close proximity to each other.

New York Mayor Bill de Blasio (D) said NYPD officers would be instructed to disperse gatherings of people in parks if they were not keeping a safe distance from each other.

“If they see anything that looks like even the beginning of a gathering, they are going to say break it up,” de Blasio said. “The message couldn’t be clearer.”

Sunday morning church services were largely nonexistent in New York, as Grace Church in the West Village rang its bells but kept its doors locked. Worshipers were invited to watch a live stream of services hosted by another Manhattan church.

Our Lady of Pompeii Church in Lower Manhattan was open, but had just two worshipers inside, each wearing masks and sitting on opposite sides of the pews.

“Oh, a church is open! It’s so hard to find a church that’s open,” said Irene Venditti, 69, as she passed by. “God’s always with us,” she said. “It’s nice to be here, but I don’t need to be here to be with God.”

Also Sunday, a number of New York-area lawmakers, including House Judiciary Committee Chairman Jerrold Nadler (D) urged the Justice Department to find ways to let more defendants out of federal jails in the city, after the Metropolitan Detention Center in Brooklyn had its first detainee test positive. Defense lawyers and other advocates have warned that the nation’s prison and jail population are particularly vulnerable to outbreaks of coronavirus.

Around New York City, local businesses and residents grappled this weekend with such a sweeping, open-ended order.

In Queens, many businesses were already shuttered Sunday, and the few that were open tried to drum up enough business to pay the bills.

At the 51st Baker & Cafe, owner Jonathan Stirling said he understood the reasons for the government order, but the effects on his business were painful.

“This is so beyond what I’ve had to deal with,” Stirling said. He’s already reduced the cafe’s hours and was making deliveries himself. “If it continues like this we can pay the payroll for this skeleton staff,” he said.

In Manhattan, Nadov Cohen spent Saturday night working at Tabouleh, a casual restaurant he owns in the Hell’s Kitchen neighborhood. By dinnertime, he’d logged just $79.20 in sales, compared to the $1,500 or more he’d make on a typical night before the pandemic.

Cohen, who already had to let his entire staff go, does not think his business will survive, in part because the business depends on the theater crowd and tourists.

He said he is still going to work not to feed the few remaining customers, but for his kids.

“It’s about seeing their father function,” he said.