President Trump clashed Tuesday with Democratic leaders Chuck Schumer and Nancy Pelosi with the cameras rolling in the Oval Office, as the president insisted he's willing to let the government shut down if Congress doesn't approve funding for his U.S.-Mexico border wall.

"If we don't have border security, we'll shut down the government," Trump said.

The highly anticipated sit-down quickly escalated, in public, as Trump allowed the press to attend the start of it. Trump began by repeatedly telling Pelosi, the House Democratic leader, his party is limited in what it can do because it will take Democratic support to pass anything through the Senate.

Schumer then raised his voice as he claimed the Senate could pass measures to keep the government running regardless.

"If it's not good [on] border security, I won't take it," Trump shot back.

Pelosi and Schumer repeatedly urged the president to take the meeting private, but not before he declared he's "proud to shut down the government for border security" and will "take the mantle."

Pelosi noted, "this has spiraled downwards."

The meeting broke up roughly a half-hour after the cameras stopped rolling. The very-public discord leaves unclear whether the two sides can come to an agreement to keep the government running before a looming Dec. 21 deadline.

Pelosi, speaking to reporters afterwards, claimed they left things “in a pretty good place.” But the White House put out a statement after the meeting saying “major disagreement remains on the issue of border security and transparency,” despite their "constructive dialogue."

Schumer and Pelosi put out a terse post-meeting statement: “We gave the president two options that would keep the government open. It’s his choice to accept one of those options or shut the government down.”

The explosive meeting with Schumer, the Senate minority leader, and Pelosi came hours after Trump threatened Tuesday to have the military “build the remaining sections” of the wall if Congress doesn’t deliver the funding. Vice President Mike Pence was also in attendance.

As Trump began discussing the details of the negotiations, Pelosi said, "I don’t think you should have a debate in front of the press." At another point, Schumer said: "Let's debate in private.”

Trump and Schumer also exchanged zingers over recent midterm elections.

“Elections have consequences, Mr. President,” Schumer said.

“And that’s why the country is doing so well,” the president shot back.

Schumer jabbed Trump over boasting that Republicans kept control of the Senate.

“When a president brags that he’s won Indiana and North Dakota, he’s in real trouble,” Schumer said.

“We did!” Trump replied. “We did win.”

After the meeting, Pelosi and Schumer signaled they won’t budge on border wall funding.

“This temper tantrum that he seems to throw will not get him his wall, and it’ll hurt a lot of people, because he will cause a shutdown,” Schumer told reporters outside the West Wing.

Congress last week temporarily averted a partial shutdown amid the funeral services for the late President George H.W. Bush, pushing the new deadline to Dec. 21. But border wall funding remains the sticking point as Trump and congressional leaders try to hammer out a government spending package. Trump wants $5 billion for the project, while Democrats are offering $1.3 billion for border security.

Earlier, Pelosi and Schumer put out a joint statement Monday arguing Trump and his party will own a government shutdown if they can’t strike a deal.

"Republicans still control the House, the Senate and the White House, and they have the power to keep government open," they said. "Our country cannot afford a Trump Shutdown," the Democrats said, adding that Trump "knows full well that his wall proposal does not have the votes to pass the House and Senate and should not be an obstacle to a bipartisan agreement."

Trump said Friday that Congress should provide all the money he wants for the wall and called illegal immigration a "threat to the well-being of every American community."

Pelosi said she and many other Democrats consider the wall "immoral, ineffective and expensive."

Schumer has previously said Democrats want to work with Trump to avert a shutdown, but said money for border security should not include the concrete wall Trump has envisioned. Instead, the money should be used for fencing and technology that experts say is appropriate, Schumer said.

Pelosi, facing a rebellion from some Democrats as she seeks to become speaker of the House again in January, also faces pressure from her base not to bend on the border wall funding fight. But more than the speaker’s gavel is at stake – Democratic votes in both the House and Senate could be critical for averting a partial shutdown.

Sixty votes are required in the Senate to overcome a filibuster. And, at least for the near-term, Republicans only have 51 members.

TRUMP THREATENS TO HAVE MILITARY BUILD BORDER WALL IF PELOSI, SCHUMER WON’T BUDGE

Republicans for the rest of the month have a comfortable majority in the House, but lack the votes on their side alone to pass a bill with or without wall money.

Pelosi and Schumer have urged Trump to support a bill that includes a half-dozen government funding bills largely agreed upon by lawmakers, along with a separate measure that funds the Department of Homeland Security at current levels through Sept. 30.

Fox News’ Chad Pergram and The Associated Press contributed to this report.