Deaths from the coronavirus in the U.S. could be in the hundreds of thousands, leading government immunologist Dr. Anthony Fauci said Sunday. He said Americans will still need to practice CDC-directed guidelines to avoid the spread of the novel coronavirus, despite earlier White House statements that the "social distancing" and other recommendations could be loosened as soon as this week.

While modeling is imperfect and it's difficult to know for sure, "looking at what we are seeing now, I would say between 100,000-200,000" deaths from coronavirus," Fauci, director of the National Institute of Allergy and Infectious Diseases, said on CNN's "State of the Union" Sunday morning. "We're going to have millions of cases."

The warnings came as the U.S. surpassed 2,000 deaths and 124,000 cases of the coronavirus. President Donald Trump backed off an earlier threat to impose a quarantine on New York and the surrounding area, instead saying Saturday night he would ask the CDC to issue a "strong Travel Advisory" to keep people in the virus' hotspots from taking the illness elsewhere.

"Quarantine will not be necessary," Trump tweeted.

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But nor will the country be able to begin reopening, as Trump earlier indicated. The White House issued a "15 days to Slow the Spread" policy March 16, and the deadline for re-evaluation is this week. The administration is also considering loosening restrictions for some areas of the country that have not yet been as hard-hit as New York, California, Washington state and other areas.

But Fauci was skeptical. In "my own opinion, looking at the way things are, I doubt if that would be the case," Fauci told CNN. "We're going to be talking about it, but obviously what you see me describe, it's a little iffy there."

A month after the first U.S. death from the coronavirus, the death rate in the United States surpassed 2,000 Saturday – double what the death count had been two days previous. Mayors and governors have been pleading with the federal government for help, but some have been fighting with a president who has expressed public anger over what he calls a lack of appreciation by some governors.

House Speaker Nancy Pelosi, Democrat of California, called for more testing and said the president's failure to take the crisis seriously has worsened the infection and death rate.

"The president – his denial at the beginning was deadly. His delaying of getting equipment to where it's needed is deadly ... I don't know what the scientists said to him: When did this president know about this and what did he know?" Pelosi said on CNN. The House Friday did final passage of a $2 trillion coronavirus disaster relief package, but the Speaker was not asked to join Trump at the signing ceremony.

Michigan Gov. Gretchen Whitmer says her state is bidding against other states and the federal government for critical equipment, such as masks.

"It's a unique situation that we have in our country right now and it's ... creating a lot more problems for all of us," she told CNN. New York City Mayor Bill de Blasio said the city had enough supplies – except ventilators – to get through April 5, but "we're going to need a reinforcement by Sunday, April 5 in all categories," including medical personnel to treat the ill.

Louisiana Gov. John Bel Edwards, too, said his state would meet its capacity for ventilators by April 5. And a few days after that, hospitals will not have enough beds.

"We remain on a trajectory, really, to overwhelm our capacity to deliver health care," the governor, a Democrat, said on ABC's "This Week." Louisiana has received just 192 ventilators, despite putting in an order for 12,000, he said.

Whitmer said she was "grateful" for recent help from FEMA and declined to criticize Trump for saying Vice President Mike Pence, who is leading the White House's coronavirus task force, should not call Whitmer or other governors who have been less than appreciative of his efforts.