The world's most powerful government has shut down after President Donald Trump and the US Congress failed to reach a deal on funding for federal agencies, highlighting America's deep political divisions.
For the first time since October 2013 - when a similar standoff that lasted 16 days kept only essential agency operations running - federal workers were being told to stay at home or in some cases to work without pay until new funding is approved.
Republican and Democratic leaders were expected to renew negotiations on Saturday (US time) in the hope of restoring government financing before Monday.
Mr Trump's inability to cut a deal despite having a Republican majority in both houses of Congress marks arguably the most debilitating setback for his administration.
For the President, this weekend was supposed to be a celebration. On the first anniversary of his presidency on Saturday, with the stock market roaring and his poll ratings finally rising, he had planned to rest at his Mar-a-Lago estate in Florida, feted by friends and admirers.
Instead, he stayed in Washington.
"This is the One Year Anniversary of my Presidency and the Democrats wanted to give me a nice present," Trump said in an early morning tweet, adding the hashtag DemocratShutdown.
Mr Trump, who in July 2016 said: "Nobody knows the system better than me, which is why I alone can fix it" has asserted that past government shutdowns were the fault of the person in the White House. After a 2013 shutdown, he said then-President Barack Obama was ultimately responsible.
As this new shutdown, the first since 2013, looked increasingly likely on Friday, Mr Trump made a last-ditch effort to behave as the kind of problem-solver he has long claimed to be.
First, he postponed a lavish $US100,000-a-couple fundraiser on Saturday, given critics would have hammered him for attending while government workers were being put on leave and many government services curtailed.
Then Mr Trump called Democrat Chuck Schumer and, after a positive conversation, invited him to a meeting at the White House in a bid to find common ground.
One person familiar with the events said the two men agreed to seek a grand deal in which Democrats would win protections from deportation for some 700,000 young undocumented immigrants known as "Dreamers" and Mr Trump would get more money for a border wall and tighter security to stem illegal immigration from Mexico.
By early evening, however, that plan was dead. The source said Mr Trump had spoken in the meantime with conservative Republicans and been hit with their objections to the deal with Schumer.
"He did not press his party to accept it," Mr Schumer said later. In a tweet he reminded Mr Trump of what the then-reality TV star said about shutdowns: "I think it would be a tremendously negative mark on the president of the United States."
Members of each party blamed the other for the shutdown, but some of the blame landed on the President.
Mr Trump blamed Democrat lawmakers in a Twitter post early on Saturday.
"Democrats are far more concerned with illegal immigrants than they are with our great military or safety at our dangerous southern border," he said. "They could have easily made a deal but decided to play Shutdown politics instead."
Well short of securing funding
The vote was 50-49, well short of the 60 needed in the 100-member chamber to vault the bill over a procedural hurdle.
Four Republicans joined most Democrats in killing the measure. A fifth Republican, Senate Majority Leader Mitch McConnell, voted "no" too, but only as part of a parliamentary manoeuvre to make it easier to bring another bill to the floor.
The immediate impact of the government shutdown was eased somewhat by its timing, starting on a weekend when most government employees normally do not work anyway.
The Defence Department said its combat operations in Afghanistan and other military activities would continue, while federal law enforcement officers also would remain on duty.
Mr Trump's administration also said it planned to keep national parks open with rangers and security guards on duty. The parks were closed during the last shutdown in 2013, which upset many tourists and resulted in the loss of $US500 million in visitor spending in areas around the parks and at the Smithsonian museums.
But without a quick deal, most day-to-day operations in the federal government will be disrupted. Hundreds of thousands of government employees will be put on temporary unpaid leave, including many of the White House's 1700 workers.
On Monday, government employees ranging from financial regulators and tax collectors to scientists and civilian staff at the Pentagon will have to stay away from work.
Early on Saturday, Mr McConnell offered up a new plan. Instead of the February 16 end date for the temporary spending bill, he proposed February 8.
Senate Democrats had argued this week for an extension of just four or five days to force both sides into serious negotiations on the immigration issue.
Open-air parks and monuments remained open in the US capital and on the National Mall preparations were under way for a second multi-city women's rights march. Some tourists appeared unaware of the shutdown while others expressed frustration at lawmakers' failure to reach a deal.