The US government was partially shutdown at midnight on Friday with President Donald Trump's demands for billions of dollars in funding for a border wall not met.
Trump insisted on Friday that if the Senate could not reach a deal with the House regarding the wall then a "very long shutdown" would commence.
It began going into Saturday in the US, just days before Christmas, and leaves government operations disrupted and federal workers absent or forced to work without pay.
Despite working late on trying to establish a deal with the Democrats and a discussion of possible compromises, there were no signs an agreement was near.
Trump is demanding $5.7bn (£4.5bn), which was passed by the House of Representatives by 217 – 185, but has so far been rejected in the Senate.
“The Democrats, whose votes we need in the Senate, will probably vote against Border Security and the Wall even though they know it is DESPERATELY NEEDED,” Trump tweeted on Friday. “If the Dems vote no, there will be a shutdown that will last for a very long time. People don’t want Open Borders and Crime!"
He is also prepared to postpone his Christmas trip to Florida as the shutdown commences.
"I hope we don't but we are totally prepared for a very long shutdown," he said during a White House event.
It is the third closure of federal agencies in 2018 and the issue may not be resolved until after the New Year, when the Democrats take control of the house.
Trump previously refused to sign a budget bill that did not include funding for the wall – one of his main promises made during his election campaign in 2015.
On Thursday night the House passed a budget bill that included $5.7bn for a wall to be built but that had little chance of passing through the Senate.
Subsequently the shutdown means that funding for nine of the 15 cabinet-level departments and dozens of agencies has expired. Around 800,000 federal workers will either be put on leave or forced to work without pay.
Democratic leaders have insisted they will not back the wall, regardless.
Senator Charles Schumer said: "The Trump temper tantrum will shut down the government, but it will not get him his wall.”