The effects of the US government shutdown are being felt across America as the White House warns federal workers will be fired en masse if Democrats don't back down.
The Trump administration has also halted funding for projects in Democrat-run states in apparent retaliation for the senate stalemate that caused the shutdown.
The shutdown, which only applies to government services deemed non-essential, took effect at midnight, local time, after senators failed to pass a spending bill to keep funding government agencies.
Democrats demanded the bill include healthcare provisions that Republicans refused to pass. They include reversals to Republican cuts, and extensions to existing tax credits for health insurance.
Republicans said the provisions would open the door to funding care for "illegal aliens", but Democrats pointed to longstanding laws that block unauthorised migrants from federal health programs.
Hundreds of thousands of US government workers will not be paid until the shutdown is over.
Some have been told to stay home; others are required to work without knowing when they will be paid.
"Lay-offs are imminent," White House press secretary Karoline Leavitt said.
Early effects
Many of the most visible early impacts of the shutdown hit tourist sites.
National attractions like the Library of Congress, US Botanic Garden and Liberty Bell have closed, and Washington's Smithsonian museums are set to shut in the next few days.
National parks are "generally" being kept open, but almost 10,000 park workers are furloughed so many visitor services have stopped.
Other government activities that have been suspended include:
- accepting new patients at the NIH Clinical Centre, America's largest health research hospital
- inspecting food and pharmaceutical production facilities
- progressing or issuing new defence contracts
- public health communications from the Centers for Disease Control
- research and analysis of economic data
So far, services such as healthcare, law enforcement, border control, public education and postal deliveries are relatively unaffected.
Members of the military will remain at their posts, and National Guard troops deployed to several cities for a "crime crackdown" have also been told to keep working.
Blame game
Unusually, Vice-President JD Vance joined Ms Leavitt for her regular White House press briefing to bolster Republican messaging in the political blame game.
"It's one thing [for Democrats] to say that we should solve the healthcare crisis for Americans," he said. "It's another thing to say that we're going to shut down the government unless we give the Democrats every single thing that they want."
He said no decisions had been made about which federal employees would be fired, and attacked Democrats for taking critical services "hostage" over policy disagreements.
"I actually don't think it's going to be that long of a shutdown," he said.
"This is a pure guess from the vice-president of the United States, because I think you already saw some evidence that moderate Democrats are cracking a little."
Democratic members of Congress say they are staying in Washington during the shutdown to negotiate with Republicans, who they accuse of disappearing on "vacations scattered across the country".
"What we're fighting for is to protect the health care of the American people, which has been under relentless assault," Hakeem Jeffries, House minority leader and leader of the House Democratic Caucus, said.
"They [Republicans] are asking Democrats to participate in doing more damage to the quality of life of everyday Americans. And we're not interested."
Elaine Kamarck, who worked in the Clinton White House during a past shutdown and is now a political analyst for the Brookings Institute think tank, said political pressure would intensify as the shutdown's effects worsened.
Ms Kamarck, a longtime member of the Democratic National Committee, predicted President Donald Trump would "cut a deal and call it a win".
"Today, nobody's going to notice this [shutdown] unless you're trying to go to a national monument or a national park," she said.
"But in a week, in two weeks, in three weeks, when your application for a small business loan comes due, when you've turned 67 years old and you're trying to get onto the Social Security system, all of a sudden this is going to start impacting real Americans.
"At that point, it's going to boomerang and explode in Donald Trump's face."
Blue states hit
Russ Vought, who runs the White House budget office, meanwhile told Republicans that federal workforce cuts would be made in a day or two, according to reports in US media.
He has already frozen almost $US18 billion ($27 billion) in funds for major New York City rail projects, widely seen as a tactic to put pressure on New York senator Chuck Schumer, who is leading the Democrats' effort in the shutdown fight.
Mr Vought said the shutdown had caused a review of the projects' contracting processes to be put on hold, and the payments would therefore not be processed.
He later announced funds for climate change projects in 16 Democrat-led states would also be cancelled. The funds totalled almost $US8 billion, he said on X.
— with in Washington DC
