Donald Trump has declared he will "shut down the government" just days before Christmas during an extraordinary on air press conference in which he clashed with Democratic leaders over a funding deal.

The US president claimed that if the Democrats will not approve funding for his border wall, he was willing to allow a lapse in federal government funding which would see large parts of the government close down.

“I am proud to shut down the government for border security. I will take the mantle, I will shut it down,” Mr Trump said.

Mr Trump was meeting with Nancy Pelosi and Chuck Schumer, the most senior Democrats in the House of Representatives and the Senate respectively, to agree on a package of funding.

But in an extraordinary turn of events, Mr Trump invited reporters into the private Oval Office negotiation and argued heatedly with the Democratic leaders in front of the cameras.

During the heated exchange Mr Trump threatened to stop funding the US government if he doesn’t get the money to continue building a wall on the border with Mexico.

"If we don’t get what we want, I’ll shut down the government," Mr Trump said during a heated exchange. "I will be the one to shut it down."

Vice President Mike Pence sat beside Mr Trump, silent and stone faced.

Swaths of federal funding will expire on December 21, forcing a partial shutdown unless a new deal can be reached.

Mr Trump wants Congress to agree to $5 billion (£3.9 billion) he says is needed to fund a large border wall along hundreds of miles of the US-Mexican border. However  Mr Schumer and Ms Pelosi have offered to extend funding at current levels, around $1.3 billion. That is less than the $1.6 billion a bipartisan Senate committee approved.

Mr Schumer and Ms Pelosi both said legislation to keep the government open and provide additional border security could pass both houses of Congress, but Mr Trump insisted major wall funding was necessary, saying "we don’t want criminals and drugs coming into our country".

Mr Trump also squabbled with the Democrats over whether wall funding could be approved in the House or Senate without Democratic votes.

"This has spiralled downwards," Ms Pelosi said in one notable moment.

The president asked whether Republicans had won the Senate in the November election. Mr Schumer, the ranking Democratic senator, retorted with a smile: "When the president brags he has won North Dakota and Indiana, he’s in real trouble".

Opponents say the wall, one of Mr Trump’s most memorable campaign promises in his 2016 election, is not only a waste of money but has been used by the president to whip up xenophobia.

Ms Pelosi, who is seeking to become House speaker when the new Congress convenes in January, said she and many other Democrats consider the wall "immoral, ineffective and expensive" and noted that Mr Trump promised during the 2016 campaign that Mexico would pay for the wall, an idea Mexico has repeatedly rejected.

Mr Trump insisted that the US military could be brought in to build his wall if Democrats will not vote for the funding.

At the Pentagon, Lieutenant Colonel Jamie Davis said there were no plans now for the US military to build sections of the wall. He added that under current law, however, the Defence Department could fund some border barrier projects "such as in support of counter-drug operations or national emergencies.”

After the meeting, White House spokeswoman Sarah Sanders said in a statement it was a "constructive dialogue" and said Mr Trump was "grateful" cameras captured him fighting to protect the border.

Back on Capitol Hill, Schumer accused Mr Trump of throwing a tantrum but said Mr Trump told the Democrats he would consider their budget proposals, Schumer told reporters.

Ms Pelosi told reporters she had asked Mr Trump to pray about resolving the dispute, recounting the biblical story of King Solomon asking God for wisdom.

But the harsh words continued during a closed meeting of House Democrats. According to an aide in the room, Ms Pelosi said Mr Trump’s fixation with building a wall was "like a manhood thing for him. As if manhood could ever be associated with him."

Despite the rancor, Senate Majority Leader Mitch McConnell, a Republican, told reporters, "I’d still like to see a smooth ending here and I haven’t given up hope that’s what we’ll have."

Ms Pelosi told reporters that later in the day that she and Mr Trump spoke by telephone, and the president said he was reviewing the offer made by Democrats during the White House meeting.