Donald Trump has threatened to shut down the US government if the Democrats refuse to vote in favour of his Mexican border wall.
The US president said if he does not get the $5bn he wants for the wall he would be "proud" to force a government shutdown.
At the time, Mr Trump was taking part in what was meant to be a pleasant photo opportunity in the Oval Office with the Senate Democratic leader Chuck Schumer and House Democratic leader Nancy Pelosi.
Mrs Pelosi seemed to strike a nerve with the president after she told him she did not want to see a "Trump shutdown" over funding for the wall.
Bickering in front of the cameras, he hit back: "If we don't get what we want, one way or the other – whether it's through you, through a military, through anything you want to call – I will shut down the government.
"I am proud to shut down the government for border security, Chuck, because the people of this country don't want criminals and people that have lots of problems and drugs pouring into our country."
Mr Schumer tried to tell the president they had a proposal that "Democrats and Republicans will support that will not shut down the government," but Mr Trump refused to listen.
"When you have walls, Chuck, it's effective, when you don't it's not," Mr Trump retorted.
After Mrs Pelosi said they should "call a halt to this", Mr Trump said: "It's not bad, Nancy – it's called transparency."
Vice president Mike Pence sat next to Mr Trump with a stony face as he remained silent during the exchange.
Sky News' foreign affairs editor, Deborah Haynes, said: "It's quite extraordinary to have what would normally be a behind the scenes incident.
"It was supposed to be a media opportunity but it turned into a clash, which gives you an insight into what things will be like in the future."
Congress is seeking to finalise spending before some government funding expires on 21 December.
Because both the House and the Senate are controlled by Mr Trump's Republican Party until next month, Democratic support is needed to pass any spending legislation.
If the government partially shuts down on 21 December, up to 600,000 government workers could be affected over the holiday season.
When Mrs Pelosi brought up Republican midterm election losses in the House, which meant the Democrats regained it, the president quickly retorted that his party won the Senate.
"When the president brags that he won North Dakota and Indiana, he's in real trouble," Mr Schumer said.
Outside the meeting, Mr Schumer told reporters Mr Trump had a "temper tantrum".
Mrs Pelosi said there could be a "Trump shutdown" for the holidays.
The two Democrats were expected to offer $1.3bn for border security in a package to extend funding for the Department of Homeland Security until 30 September next year.
A bipartisan Senate committee had approved a larger package of $1.6bn.
If the shutdown happens it would not be the first time during Mr Trump's presidency, with thousands of workers forced to stay at home without pay for three days in January after a Senate stalemate which resulted in funding not being released.
With the 51 Republicans needing 60 votes to pass the package, Democrats refused to support it as they demanded help for "Dreamers" – more than 700,000 immigrants who entered the US illegally as children.
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Hundreds of thousands of defence workers, park rangers and business regulators were unable to work, with landmarks including the Statue of Liberty closed to the public.
It ended after Democrats agreed to drop their objections in return for a Republican assurance to look at the Deferred Action for Childhood Arrivals (DACA) programme to protect the Dreamers.