WASHINGTON — President Donald Trump and Democrats are trading blame for the partial government shutdown but doing little substantive talking with each other, as the disruption in federal services and public employees’ pay slogs into another weekend.

Trump upped the brinkmanship by threatening anew to close the border with Mexico to press Congress to cave to his demand for money to pay for a wall. Democrats vowed to pass legislation restoring the government as soon as they take control of the House on Thursday, but that won’t accomplish anything unless Trump and the Republican-controlled Senate go along with it.

Cooped up in the White House after canceling his planned vacation to his private Florida club, Trump tweeted Saturday that he’s “in the White House waiting for the Democrats to come on over and make a deal on Border Security.” But there has been little direct contact between the sides during the stalemate, and Trump did not ask Republicans, who hold a monopoly on power in Washington for another five days, to keep Congress in session.

The president did leave the White House on Friday night to join the three men at the center of the negotiations, Vice President Mike Pence, Trump’s senior adviser and son-in-law Jared Kushner and acting chief of staff Mick Mulvaney, for dinner at Pence’s residence at the Naval Observatory.

As he called for Democrats to negotiate on the wall, Trump brushed off blame that his administration bore any responsibility for the recent deaths of two migrant children in Border Patrol custody. Trump claimed the deaths were “strictly the fault of the Democrats and their pathetic immigration policies that allow people to make the long trek thinking they can enter our country illegally.” His comments on Twitter came as his Homeland Security secretary met with medical professionals and ordered policy changes meant to better protect children detained at the border.

Meanwhile, the effects to the public of the impasse grew as the Environmental Protection Agency, which had the money to function a week longer than some agencies, implemented its shutdown plan at midnight Friday night. EPA spokeswoman Molly Block said many of the agency’s 14,000 employees were being furloughed, while disaster-response teams and certain other employees deemed essential would stay on the job. That includes workers needed for preventing immediate public health threats at more than 800 Superfund hazardous-waste sites.

Also running short on money: the Smithsonian Institution, which said its museums, art galleries and zoo in the capital will close starting midweek if the partial shutdown drags on.

But federal flood insurance policies will continue to be issued and renewed, in a reversal prompted by pressure from lawmakers, said Republican Sen. Marco Rubio of Florida.

Trump appeared no closer to securing money for his signature border wall, which he vowed during the campaign that he would make Mexico pay for. He’s failed to do so. Now Democratic leaders are adamant that they will not authorize money for the project, calling it wasteful and ineffective. They show no signs of bending, either.

“We are far apart,” White House press secretary Sarah Sanders told CBS on Friday.

Trump tweeted: “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 also threatened to cut off U.S. aid to El Salvador, Guatemala and Honduras, among countries he deems have not done enough to combat illegal immigration.

He’s made similar threats in the past without following through, and it is Congress, not the president, that appropriates aid money.

The shutdown is forcing hundreds of thousands of federal workers and contractors to stay home or work without pay.

Mulvaney said Democrats are no longer negotiating with the administration over an earlier offer by the White House to accept less than the $5 billion Trump wants for the wall.

Democrats said the White House offered to accept $2.5 billion for border security, but that Senate Democratic leader Chuck Schumer told Vice President Mike Pence that it wasn’t acceptable. It was also not guaranteed that Trump would settle for that amount.

“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.

Mulvaney said Schumer was “really interested in doing a deal and coming to some sort of compromise” but he understood that Pelosi was at risk of losing the speakership of the House if she went along. “So we’re in this for the long haul,” he said.

In fact, Pelosi has all but locked up the support she needs to win the speaker’s gavel after the new Congress convenes on Thursday, and there has been no sign that she and Schumer are in conflict.

“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. But that alone won’t solve the shutdown, absent Senate approval and Trump’s signature.

Pelosi spokesman Drew Hammill added that Democrats are united against the wall and won’t seriously consider any White House offer unless Trump backs it publicly because he “has changed his position so many times.”

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.