At the same time, the president has toggled between sparring with several of the Democratic governors on the front lines of the outbreak and assuring the public that they are getting along smoothly — even broadcasting their occasional praise of him in campaign ads.

The jarring shifts in the president’s sentiments were evident Friday, when Trump struck a confusing tone regarding his view of states’ rights at the White House coronavirus task force’s daily news briefing.

“I like to allow governors to make decisions without overruling them, because from a constitutional standpoint, that’s the way it should be done,” he said. “If I disagreed, I would overrule a governor, and I have that right to do it. But I’d rather have them — you can call it ‘federalist,’ you can call it ‘the Constitution,’ but I call it ‘the Constitution’ — I would rather have them make their decisions.”

But pressed on what grounds he would have to reopen the country given his own refusal to impose a nationwide stay-at-home order, Trump was less deferential. “The states can do things if they want. I can override it if I want,” he said.

The president’s tweets Monday appeared to represent a similar attempt to flex his executive muscle as the White House weighs whether to extend stringent social-distancing guidelines beyond April 30.

Trump is anxious to reverse a dramatic slide in America’s economic fortunes that has sent jobless claims soaring and led to trillions of dollars in fiscal and monetary stimulus, and his aides are examining whether certain parts of the country could be safe to open in the near future.

Last week, Treasury Secretary Steven Mnuchin said the administration was eyeing May 1 as a target date for restarting the U.S. economy, but health officials stressed that much of the country must remain in lockdown even as they sounded increasingly optimistic notes about the success of the federal mitigation measures.

“There’s no doubt that we have to reopen correctly,” Dr. Robert Redfield, director of the Centers for Disease Control and Prevention, said Monday. “It’s going to be a step-by-step, gradual process. It’s got to be data-driven, and as I said, I think it would be community-by-community, county-by-county.”

At least one federal agency is already having conversations about what business operations would look like when people head back to work at government buildings and how to communicate to employees about the uncertain return to normal, according to a U.S. government official familiar with the matter.

The Office of Personnel Management and the Office of Management and Budget have had continuous discussions about how to unwind the telework guidance that has been issued to federal workers when the time is right, another Trump administration official said.

When it comes to states, however, the president’s legal prerogative to order them to relax their lockdown policies is dubious. The federal government lacks the “police power” authority that states have to regulate their own citizens, including by issuing orders to stay home in an effort to stem the spread of the coronavirus.

What federal powers do exist in this area stem from the central government’s authority to regulate interstate and international commerce. Laws passed on that premise give officials at the CDC the ability to quarantine travelers, as well as planes, trains and automobiles moving between states.

Those powers may even extend to cordoning off an infected area or state against the wishes of local officials, particularly if local infection controls are deemed to be failing. Still, there exists no federal law empowering Trump to force a governor to rescind or loosen a stay-at-home order.

At the margins, the president might be able to undermine such decrees by trying to withhold federal aid or by ordering large numbers of federal workers and contractors to ignore the lockdown policies. Attorney General William Barr sent federal law enforcement officials a memo last month reminding them of their exemption from the state and local controls when performing work duties.

“The President can *informally* put pressure on local/state governments. He can mess with emergency funding. And he can even order the federal workforce back to their offices,” tweeted University of Texas law professor Stephen Vladeck. “But largely because he’s left so much to local authorities so far, this, too, is ultimately up to them.”

This opinion, widely held among legal scholars, did not stop acting Director of National Intelligence Richard Grenell from sharing on Instagram an image of the Constitution and the caption, “SIGNED PERMISSION SLIP TO LEAVE YOUR HOUSE.”

After a reporter noted the post, observing in a tweet that it seemed the ODNI chief “isn’t a fan of the stay at home orders,” Grenell replied, “‘Seems’ Grenell is a fan of the Constitution to me.”

Gov. Andrew Cuomo of New York — the epicenter of the outbreak in the U.S. — asserted Monday that any potential economic restart should be approached as a regional issue, and teased an announcement later in the afternoon with the governors of Connecticut, Delaware, New Jersey, Pennsylvania and Rhode Island.

“The optimum is to have as coordinated a regional plan as you can,” he said. “It is smarter for everyone, for people of their state and for the people of my state, and this is a time for smart, competent, effective government. Nothing else matters.”

Cuomo has pushed back forcefully against the president’s calls to reopen the economy in recent days, a sign that the White House will meet resistance in a state that has both suffered the most deaths from the coronavirus and is a key piston in America’s economic engine.

“I understand the need to bring back the economy as quickly as possible,” the governor said Saturday. “I understand people need to work. I also know we need to save lives, and we have. One cannot be at the expense of the other.”

Marie J. French and Daniel Lippman contributed to this report.