The US Government has shut down for the first time since 2018 after a long-running standoff over a spending Bill failed to reach a breakthrough.
Donald Trump's Republicans had pushed to pass a Bill to fund the US public sector - with the President's eyes on cutting needless spending.
However, his party's 53 seats in the Senate were not enough to pass it.
Sixty votes were required to pass a Bill like this, and though a few Democrats ended up siding with Mr Trump, it failed to get over the line.
Three Democrats - John Fetterman, Catherine Cortez Masto, and Angus King - voted with a majority of Republicans for the Bill, which failed 55 to 45.
Republican Senator Rand Paul voted against it.
Donald Trump's Republicans had pushed to pass a Bill to fund the US public sector
|GETTY
Starting at 5am BST, a string of non-essential publicly-funded bodies in the US had their taps switched off.
These include the US food assistance programme, taxpayer-funded pre-schools, student loans, food inspections, and operations at national parks.
Also set to be impacted are the release of a much-anticipated September employment report, air travel, scientific research, and pay for US troops.
Congressional trips abroad will also be cancelled during the shutdown.
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Starting at 5am BST, a string of non-essential publicly-funded bodies in the US had their taps switched off
|REUTERS
A staggering 750,000 federal workers will now be placed on furlough - a daily cost of $400million (£297million).
Over on the markets, Wall Street futures slipped while "safe haven" asset gold reached a record high after the shutdown was confirmed.
In Asia, stocks wavered as investors braced for delays in the release of key data and the impact of job losses.
Ahead of the deadline, the White House branded the chaos a "Democrat shutdown" and warned that Americans "do not agree with Democrats' actions".
On Wednesday, the Senate is expected to vote on the same Bill again. If it cannot find a breakthrough, more votes will follow into the weekend - until either a deal is struck or Democrats agree to the Government's plans.
Earlier on Tuesday, the President said his Republicans did not want a shutdown - but vowed they would inflict pain if one went through.
"We can do things during the shutdown that are irreversible, that are bad for them and irreversible by them, like cutting vast numbers of people out, cutting things that they like, cutting programs that they like," Mr Trump said.
Vice President JD Vance, meanwhile, said: "If you look at the original they did with this negotiation, it was a $1.5trillion spending package, basically saying the American people want to give massive amounts of money, hundreds of billions of dollars to illegal aliens for their healthcare, while Americans are struggling to pay their health care bills.
"That was their initial foray into this negotiation. We thought it was absurd."
Mr Trump had shared an AI-generated video of Chuck Schumer (right) and Hakeem Jeffries (left) after he met with the pair
|TRUTH SOCIAL
But the Senate's Democrat leader Chuck Schumer had said: "All they want to do is try to bully us. And they're not going to succeed," after a meeting with the President on Monday.
After the same meeting, Mr Trump had shared an AI-generated video of Mr Schumer raging at Democrats.
In it, the fake video showed Mr Schumer saying: "We have no voters any more because of our woke trans bulls**t. Not even black people want to vote for us any more... We need new voters - if we give all these illegal aliens free healthcare, we might be able to get them on our side so they can vote for us."
Next to him stood House Democrat leader Hakeem Jeffries - sporting a "Photoshopped" sombrero and moustache.