Agreement eludes Washington in the waning days of the Republican monopoly on power, and that sets up the first big confrontation between Trump and newly empowered Democrats. Trump is sticking with his demand for money to build a wall along the southern border, and Democrats, who take control of the House on Jan. 3, are refusing to give him what he wants.

Trump worked to escalate the showdown Friday, reissuing threats to close the U.S.-Mexico border to pressure Congress to fund the wall and to shut off aid to three Central American countries from which many migrants have fled.

"We will be forced to close the Southern Border entirely if the Obstructionist Democrats do not give us the money to finish the Wall & also change the ridiculous immigration laws that our Country is saddled with," he wrote in one of a series of tweets.

The president also signaled he was in no rush to seek a resolution, welcoming the fight as he heads toward his own bid for re-election in 2020. He tweeted Thursday evening that Democrats may be able to block him now, "but we have the issue, Border Security. 2020!"

Incoming acting chief of staff Mick Mulvaney said Trump had canceled his plans to travel to Florida to celebrate New Year's at his private Mar-a-Lago club.

The shutdown is forcing hundreds of thousands of federal workers and contractors to stay home or work without pay, and many are experiencing mounting stress from the impasse. It also is beginning to pinch citizens who count on public services. Gates are closed at some national parks, new farm loans will be put on hold beginning next week, and in New York, the chief judge of Manhattan federal courts suspended work on civil cases involving U.S. government lawyers, including several civil lawsuits in which Trump himself is a defendant.

The Smithsonian Institution also announced that museums and galleries popular with visitors and locals in the nation's capital will close starting midweek if the partial shutdown drags on.

The Environmental Protection Agency will keep disaster-response teams and other essential workers on the job as it becomes the latest agency to start furloughing employees in the government shutdown. Spokeswoman Molly Block says the EPA will implement its shutdown plan at midnight Friday. That will mean furloughing many of its roughly 14,000 workers.

Sen. Marco Rubio, R-Fla., released a statement applauding a decision by the administration to reverse new guidance issued by the Department of Homeland Security that prevented the Federal Emergency Management Agency from writing or renewing National Flood Insurance Program policies during the current government shutdown. He said it was important that people could continue to get and maintain their flood insurance.

With another long holiday weekend coming and nearly all lawmakers away from the Capitol there is little expectation of a quick fix.

"We are far apart," White House press secretary Sarah Sanders told CBS on Friday, claiming of Democrats, "They've left the table all together."

Mulvaney said Democrats are no longer negotiating with the administration over an earlier offer to accept less than the $5 billion Trump wants for the wall. Democrats said the White House offered $2.5 billion for border security, but that Senate Democratic leader Chuck Schumer told Vice President Mike Pence it wasn't acceptable.

"There's not a single Democrat talking to the president of the United States about this deal," Mulvaney said Friday

Speaking on Fox News and later to reporters, he tried to drive a wedge between Democrats, pinning the blame on House Democratic leader Nancy Pelosi.

"My gut was that (Schumer) was really interested in doing a deal and coming to some sort of compromise. But the more we're hearing this week is that it's Nancy Pelosi who's preventing that from happening," he said, alleging that if Pelosi "cuts a deal with the president of any sort before her election on January 3rd she's at risk of losing her speakership, so we're in this for the long haul."

Pelosi has all but locked up the support she needs to win the gavel on Jan. 3 and there is also no sign of daylight between her and Schumer in the negotiations over government funding.

Mulvaney added of the shutdown: "We do expect this to go on for a while."

Democrats brushed off the White House's attempt to cast blame.

"For the White House to try and blame anyone but the president for this shutdown doesn't pass the laugh test," said Justin Goodman, a spokesman for Schumer.

Pelosi has vowed to pass legislation to reopen the nine shuttered departments and dozens of agencies now hit by the partial shutdown as soon as she takes the gavel, which is expected when the new Congress convenes.

Pelosi spokesman Drew Hammill added that Democrats "are united against the President's immoral, ineffective and expensive wall" and said Democrats won't seriously consider any White House offer unless Trump backs it publicly because he "has changed his position so many times."

"While we await the President's public proposal, Democrats have made it clear that, under a House Democratic Majority, we will vote swiftly to re-open government on Day One," Hammill said in a statement.

But even that may be difficult without a compromise because the Senate will remain in Republican hands and Trump's signature will be needed to turn any bill into law.

"I think it's obvious that until the president decides he can sign something — or something is presented to him — that we are where we are," said Sen. Pat Roberts, R-Kan., who opened the Senate on Thursday for a session that only lasted minutes.

Trump had said during his campaign that Mexico would pay for his promised wall, but Mexico refuses to do so. It was unclear how Trump's threat to close the border would affect his efforts to ratify an amended North American free trade pact.

He has repeatedly threatened to cut off U.S. aid to countries that he deems have not done enough to combat illegal immigration, but thus far he's failed to follow through. Experts have warned that cutting off aid money to El Salvador, Guatemala and Honduras could actually exacerbate the problem by worsening the poverty and violence that push many migrants to leave.

And it is Congress, not the president, which appropriates aid money.

Mexican President Andres Manuel Lopez Obrador reacted cautiously to Trump's threat to close the border, calling it an "internal affair of the U.S. government."

"We are always seeking a good relationship with the United States. We do not want to be rash," he said.