Trump spars with top Democrats in Oval Office over border wall

US President Donald Trump openly fought with the top two Democratic politicians at an Oval Office meeting on Tuesday about government funding, throwing into question whether a deal was possible before a deadline later this month.

In a rare public argument, Trump bickered with US Senate Democratic Leader Chuck Schumer and House Democratic Leader Nancy Pelosi about funding for his proposed border wall.

"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," Trump said as the heated argument drew near a close.

"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," he said before reporters left the room.

Congress is seeking to finalise spending before some federal government funding expires on December 21. While Trump's fellow Republicans control both the House and the Senate until next month, Democratic support is needed to pass any spending legislation.

The president has called for $5 billion to fund the barrier along the US-Mexico border, a campaign promise that he has made into a focal point. He ended the argument by saying he was willing to make good on his repeated threat to shut down the federal government over the issue.

In a poll related on Tuesday by NPR/PBS NewsHour and Marist Poll, 57% of Americans said Trump should compromise on the wall to avoid a government shutdown. About 36% said he should not.

Tuesday's spat was the first time Trump met Pelosi and Schumer since the Democrats won control of the House of Representatives in the November 6 congressional elections - a rocky start to the relationship the White House will have with the opposition party, with which it needs to deal to advance any priorities. 

The fight kicked off when Pelosi told Trump that Americans did not want to see a "Trump shutdown," touching a nerve. Trump cut off Pelosi, arguing that he could not advance a funding bill without Democratic votes in the Senate.

"I don't think we should have a debate in front of the press on this," Pelosi said.

"We're doing this in a very friendly manner," Trump said, as Vice President Mike Pence sat beside him, silent and stony-faced.

Senior White House staff watched the melee from the corners of the room, among them Jared Kushner and Ivanka Trump, outgoing Chief of Staff John Kelly, immigration adviser Stephen Miller, and Shahira Knight, his legislative director.

Then Schumer brought up the "Pinocchios" that Trump had been awarded by the Washington Post for misstatements on the issue and accused him of wanting to get his own way.

"Let's call a halt to this," Pelosi said as the two New Yorkers went at it.

"It's not bad, Nancy - it's called transparency," Trump said.

When Pelosi brought up Republican election losses in the House, Trump quickly retorted that his party won the Senate.

"When the president brags that he won North Dakota and Indiana, he's in real trouble," Schumer said to the astonished press capturing the back-and-forth.

Trump has sought to sow fear over thousands of migrants and refugees who have recently arrived at the border as part of an exodus, initially dubbed the Central American caravan. More than 6,000 people are currently waiting in Tijuana to file for asylum in the US. Rights groups estimate many will have to wait up to two months before being allowed in the US to submit their claims.

He has sent more than 5,000 troops to the border to offer logistic support to border patrol agents. The Department of Defense approved a plan to extend the deployment of about 4,000 active-duty troops through January. 

Prior to Tuesday's public spat, Trump said the military would build his promised border wall if Congress did not sign off his funding proposal. 

It was unclear how Trump would try to use the US Department of Defense to build the wall, given that defence and military construction appropriation bills were signed into law for the 2019 fiscal year without any wall funding.