President Trump’s inaccurate assertion that he has “total” authority to reopen a nation shuttered by the coronavirus is igniting a fresh challenge from governors scrambling to manage their states and highlighting a Republican Party reluctant to defy a president who has relished pushing the boundaries of executive power.

The president’s claim, first conveyed in a tweet Monday morning and underscored at a White House news conference and subsequent social media posts, caught his aides off guard and prompted them to study whether Trump would have such authority in a time of emergency like the ongoing pandemic.

Republicans were largely tepid in their criticism of Trump’s expansive views on his power, which he has wielded throughout his presidency as he circumvented the legislative branch on matters of spending and subpoenas, while enjoying decisions in which he maintained universal authority such as issuing pardons. Trump has also issued a multitude of executive orders while relying heavily on myriad acting administration officials rather than subjecting them to the Senate confirmation process.

President Trump said April 14 he will authorize all 50 governors to determine when their individual states will be reopened after the coronavirus crisis. (The Washington Post)

At a White House briefing late Tuesday, Trump offered conflicting statements about which entity had the authority to reopen, seeming to backtrack from his claim Monday but at the same time insisting the federal government would have the final say.

“The governors are responsible. They have to take charge,” said Trump, who added that some states want to reopen now and probably can before May 1, while others aren’t there yet. He said that if a state with many cases tries to reopen early, the federal government might step in.

“If we disagree with it, we’re not going to let it open,” he said, before adding, “We’re there to help. But we’re also there to be critics.”

Earlier in the day, Trump’s comments on reopening the nation were challenged by his presumptive Democratic rival this fall, former vice president Joe Biden, and also by prominent governors overseeing the public health crisis in their states such as New York Gov. Andrew M. Cuomo, who in his daily news conference Tuesday skewered at length Trump’s position as wildly off-base from the Constitution.

Cuomo said the president’s claim of total authority is “not an accurate statement,” because the basic principle of federalism is enshrined in the Constitution, in which powers not given to the federal government remain with the states.

“The statement that he has total authority over the states and the nation cannot go uncorrected,” Cuomo said. “There are many things that you can debate in the Constitution because they’re ambiguous. This is not ambiguous.”

Later Tuesday in his own remarks, California Gov. Gavin Newsom (D) was less pointed toward Trump but nonetheless unequivocal, tweeting: “When it comes to reopening, SCIENCE — not politics — must be California’s guide.” Newsom outlined six factors he will consider in doing so, including protecting communities from the spread of the virus and ensuring that hospitals could handle any surge in cases.

The fresh power struggle between the federal government and state officials came as the toll of the pandemic continued to grow, with more than 25,000 people dead from the virus in the United States and more than 600,000 confirmed to be infected.

The International Monetary Fund said Tuesday that the pandemic is causing the worst economic downturn since the Great Depression of the 1930s. It is also inflicting acute pain in the medical sector, which continues to struggle with supplies and personnel becoming sick, with the Centers for Disease Control and Prevention saying Tuesday that 9,000 health care workers have tested positive.

In another assertion of authority, Trump said he would halt funding to World Health Organization while a review was conducted. He has criticized the organization for its slow response in the early days of the outbreak, but by Jan. 30, the organization declared a global health emergency, after which the president continued to play down the outbreak and compared it with seasonal flu.

Governors also began outlining their strategy for reopening their states in the coming weeks and months, while a consortium of seven East Coast states continued a plan to explore how and when to lift restrictions in their geographically aligned states.

Ohio Gov. Mike DeWine (R) was among the state leaders who made clear Tuesday that the facts on the ground must dictate when the current restrictions can begin to ease.

“This monster is still going to be with us at least until we get a vaccine,” DeWine, who has said his state has had a good working relationship with federal officials so far, said at a Tuesday news conference. “It’s not going away, and that’s the sad news. . . . We are 12-18 months away from this going away. We’re going to have to live with it..”

Two White House officials said there was no broader planning for Trump’s comments that he had “total” authority and that they were both surprised by his tweets to that effect Monday. There was no legal underpinning for the remarks in advance, said the officials, who spoke on the condition of anonymity to talk frankly, and “it is widely viewed with skepticism in the building that we should be doing this.”

The White House Counsel’s Office is studying what authority the president actually does have during a national emergency, according to the officials. But the operating plan in the White House is not to try to force any state to reopen, although one senior White House official said they had been in contact with some states — such as Texas, Mississippi and Tennessee — about reopening sooner rather than later.

“I am almost positive James Madison fell off a cloud somewhere today when Trump said that,” said Dan Eberhart, a Republican donor. “The founders of the republic stitched together a complicated game of chess to ensure our president was a very weak king who could be simultaneously slowed down by the legislature, judiciary and federalism. His authority is far from total.”

Another prominent GOP donor, speaking on the condition of anonymity to discuss private deliberations, said there was an effort “to talk him into a better place.”

One official said Trump is frustrated that the governors are getting so much credit and no blame while he gets all the blame and none of the credit. He particularly complains about Cuomo, this official said.

“Cuomo’s been calling daily, even hourly, begging for everything, most of which should have been the state’s responsibility, such as new hospitals, beds, ventilators, etc.,” Trump tweeted earlier Tuesday. “I got it all done for him, and everyone else, and now he seems to want Independence! That won’t happen!”

Trump has said repeatedly that the federal government is merely a backup to the states and that the onus is on the governors to deal with the pandemic.

Sen. Lindsey O. Graham (R-S.C.) said in a recent interview that “at the end of the day, it will be the governors that make these decisions.”

One Republican ally close to the president said Trump did not initially want to be associated with decisions to close down the government because “closing is bad news, and opening is good news.” And he spoke with governors such as Florida’s Ron DeSantis (R) who were skeptical, said this person, who spoke on the condition of anonymity to describe private conversations.

Trump was happy to accept the argument from some advisers that he should invoke federalism, and the president repeatedly emphasized states’ rights when questioned by reporters in recent weeks why he was not instituting a national stay-at-home order. But he sees a political triumph in reopening the economy and wants credit for it, this person said.

In a tweet Monday, Biden said that he is “not running for office to be King of America.”

“I respect the Constitution,” Biden said. “I’ve read the Constitution. I’ve sworn an oath to it many times. I respect the great job so many of this country’s governors — Democratic and Republican — are doing under these horrific circumstances.”

Within the GOP, Trump’s biggest challenge to his exertion of executive power came last year, when a dozen GOP senators voted to reject an emergency declaration the president issued to take taxpayer dollars from the military and other accounts for a border wall that Congress had denied.

Of that dozen, two — Sens. Rand Paul (Ky.) and Marco Rubio (Fla.) — issued comments Tuesday, both stressing that states should retain the power to regulate their own activities. Sen. Lisa Murkowski (R-Alaska) said in a statement: “I respect the authorities of the office of the presidency. I also recognize that it will take all of us — elected leaders and citizens — to effectively stop the spread of this virus.”

A spokeswoman for Sen. Rob Portman (R-Ohio) pointed to his remarks from a Fox Business interview earlier Tuesday in which he said the matter was not just up to elected officials “deciding when it’s time and coming up with some arbitrary deadline,” but the science and whether people feel safe leaving their homes.

Aides to two others — Utah Sens. Mitt Romney and Mike Lee — said the senators would have no response. None of the other six responded to requests for comment. They were Sens. Lamar Alexander (Tenn.), Roy Blunt (Mo.), Susan Collins (Maine), Jerry Moran (Kan.), Patrick J. Toomey (Pa.) and Roger Wicker (Miss.).

At least two other prominent elected GOP lawmakers, past and present — Rep. Liz Cheney (R-Wyo.), the third-ranking leader among House Republicans, and Republican-turned independent Rep. Justin Amash (Mich.) — challenged Trump’s notion.

Cheney, whose father, Richard B. Cheney, had pushed for broad executive authority as vice president in George W. Bush’s administration, cited the text of the 10th Amendment in a tweet: “The powers not delegated to the United States by the Constitution, nor prohibited by it to the States, are reserved to the States respectively, or to the people.”

But other GOP lawmakers questioned about Trump’s bold claim, an assertion refuted by constitutional experts, were reluctant to challenge the president.

Rep. Steve Scalise (R-La.), the No. 2 House Republican, argued in a Fox News interview Tuesday that states had largely taken their cue from Trump and the federal government over the past two months, particularly when it comes to social distancing guidelines.

“When the president said that, you saw almost every governor in the country take that cue and say, ‘Okay, we’re going to institute a new set of policies,’ ” Scalise said. “And so, while the president hasn’t said every state has to do this, he’s been setting the guidance using the experts from CDC and other agencies, and then you see states following suit.”

A spokesman for Maryland Gov. Larry Hogan (R) on Tuesday declined to comment beyond the governor’s remarks to CNN on Monday in which he said governors were best positioned to make the ultimate decision on when their states can safely resume everyday activities.

“It’s not my understanding of the Constitution,” Hogan said in the CNN interview of Trump’s interpretation of his own powers.

Devlin Barrett, Ovetta Wiggins, Felicia Sonmez, Mike DeBonis, Samantha Pell and Brittany Shammas contributed to this report.