President Donald Trump signed a 900 billion dollar (£664 billion) pandemic relief package on Sunday, ending days of drama over his refusal to accept the bipartisan deal that will deliver long-sought cash to businesses and individuals and avert a federal government shutdown.
The massive bill includes 1.4 trillion dollars (£1.03 trillion) to fund government agencies through to September and contains other end-of-session priorities such as money for cash-starved transit systems and an increase in food stamp benefits.
Mr Trump announced the signing in a statement that spoke of his frustrations with the Covid-19 relief for including only 600-dollar (£443) cheques to most Americans instead of the 2,000 dollars (£1,476) that his fellow Republicans rejected.
He also complained about what he considered unnecessary spending by the government at large. But Mr Trump's eleventh-hour objections created turmoil because politicians had thought he was supportive of the bill, which had been negotiated for months with White House input.
"I will sign the Omnibus and Covid package with a strong message that makes clear to Congress that wasteful items need to be removed," Mr Trump said in the statement.
While the president insisted he would send Congress "a redlined version" with items to be removed under the rescission process, those are merely suggestions to Congress. The bill, as signed, would not necessarily be changed.
Politicians now have breathing room to continue debating whether the relief cheques should be as large as the president has demanded. The Democratic-led House supports the larger cheques and is set to vote on the issue on Monday, but it is expected to be ignored by the Republican-held Senate where spending faces stern opposition.
Republicans and Democrats swiftly welcomed Mr Trump's decision to sign the bill into law.
"The compromise bill is not perfect, but it will do an enormous amount of good for struggling Kentuckians and Americans across the country who need help now," said Senate Majority Leader Mitch McConnell, referencing his home state. "I thank the President for signing this relief into law."
Democrats are promising more aid to come once President-elect Joe Biden takes office, but Republicans are signalling a wait-and-see approach.
In the face of growing economic hardship, spreading disease and a looming shutdown, politicians on Sunday had urged Mr Trump to sign the legislation immediately, then have Congress follow up with additional aid.
Aside from unemployment benefits and relief payments to families, money for vaccine distribution, businesses, cash-starved public transit systems and more is on the line. Protections against evictions also hung in the balance.
"What the president is doing right now is unbelievably cruel," said independent senator Bernie Sanders. "So many people are hurting. It is really insane and this president has got to finally ... do the right thing for the American people and stop worrying about his ego."
Republican senator Pat Toomey of Pennsylvania said he understood Mr Trump "wants to be remembered for advocating for big cheques, but the danger is he'll be remembered for chaos and misery and erratic behaviour if he allows this to expire."
The same point was echoed by Maryland governor Larry Hogan, a Republican who has criticised Mr Trump's pandemic response and his efforts to undo the election results. "I just gave up guessing what he might do next," he said.
Republican representative Adam Kinzinger of Illinois said too much was at stake for Mr Trump to "play this old switcheroo game".
"I don't get the point," he said. "I don't understand what's being done, why, unless it's just to create chaos and show power and be upset because you lost the election."
Washington had been reeling since Mr Trump turned on the deal. Fingers pointed at administration officials, including Treasury Secretary Steven Mnuchin, as lawmakers tried to understand whether they were misled about Mr Trump's position.