President Trump and White House officials pressed congressional Republicans on Sunday to use the looming threat of a government shutdown to win funding for a wall along the border between the United States and Mexico, a top priority for the administration as it nears the symbolic 100-day mark.

Trump wants funding to be included in a spending measure that would keep the government open past April 28, a determined effort that has prompted a possible standoff with lawmakers in both parties, who hope to avert a federal closure next weekend.

Trump’s push for fast action on his pledge to build the border wall is part of a mounting and, at times, tense scramble inside the administration to kick-start the president’s agenda, even if it risks dire political consequences. It follows weeks of frustration within the White House over inaction and stalemates on Capitol Hill over big-ticket items such as health care and tax cuts.

White House Chief of Staff Reince Priebus said in an interview Sunday with The Washington Post that the president and his advisers remain “strong” in their commitment to securing funding for border security and a wall.

“This is what the president ran on,” Priebus said. “We want to get to a place this week where ­border-security money is being directed to the Department of Homeland Security so that we can begin surveillance and preliminary work, and then we will keep working on getting DHS what it needs for the structure.”

“The burden to keep it open is on the Republicans,” House Minority Leader Nancy Pelosi (D-Calif.), above, said Sunday on NBC’s “Meet the Press.” “Building a wall is not an answer. Not here or any place.” (Pablo Martinez Monsivais/AP)

The timing promises a week of high drama on the Hill. The Senate returns Monday night, and the House returns Tuesday from a two-week recess, leaving just three days when both chambers will be in session to wrangle out a funding agreement. Negotiators worked throughout the break, but thus far a deal has not been struck.

The wall, which experts say would cost $21.6 billion and take 3½ years to construct, has emerged as a crucial sticking point for the White House, with the president insisting privately and publicly that progress toward its funding and eventual construction must be showcased this week.

“Congress is right to be nervous, but that’s Trump’s style to be aggressive, ambitious, right out of ‘The Art of the Deal,’ ” said William J. Bennett, a conservative commentator and close friend of House Speaker Paul D. Ryan (R-Wis.). “Everyone seems to be getting used to that and how Trump doesn’t want the half loaf but the whole loaf.”

[Trump and his aides take hard line on border wall, as threat of government shutdown looms]

In a tweet Sunday, Trump elbowed Democrats who have resisted his call to include wall funding. He chastised them for not wanting “money from the budget going to the border wall despite the fact that it will stop drugs” and gang activity, in his view.

(Jenny Starrs/The Washington Post)

Trump added that he would continue to ask Mexico to pay for the project, another bold proclamation he made during the campaign. Meanwhile, he said, he will press Congress for funding “so we can get started early” on the “badly needed border wall.”

It remained unclear Sunday whether moderates within the GOP could persuade the White House to avoid a shutdown. Democrats have insisted that they will not vote for any spending bill that gives the White House money or flexibility to begin construction of a border barrier. They believe that the GOP will have to either abandon Trump’s demand or assume political responsibility if a shutdown occurs.

“The burden to keep it open is on the Republicans,” House ­Minority Leader Nancy Pelosi (D-Calif.) said Sunday on NBC’s “Meet the Press.” “Building a wall is not an answer. Not here or any place.”

Inside the White House on Sunday, West Wing aides made calls to congressional allies, while the president tweeted and reached out to several advisers, according to three officials who spoke on the condition of anonymity because they were not authorized to comment publicly.

Trump’s tweets included a shot at Democrats in which he drew parallels between border-wall funding and continued federal payments for subsidies under the Affordable Care Act. Some Trump associates said that they believe Democrats may be willing to deal on border funding if those payments are put on the table this week during cross-party talks.

“ObamaCare is in serious trouble. The Dems need big money to keep it going — otherwise it dies far sooner than anyone would have thought,” Trump tweeted. He later followed: “The Democrats don’t want money from budget going to border wall despite the fact that it will stop drugs and very bad MS 13 gang members.”

The tweets did little to assuage concerns created earlier in the day when White House budget director Mick Mulvaney suggested that Trump might not sign a spending bill that does not meet his demands.

“Will he sign a government funding bill that does not include funding for the border wall?” Chris Wallace, host of “Fox News Sunday,” asked Mulvaney during a televised interview.

“We don’t know yet,” Mulvaney responded.

Mulvaney said that the White House expects Democrats to cave on the border wall in exchange for guaranteed payments under the ACA.

But Pelosi and Senate Minority Leader Charles E. Schumer (D-N.Y.) have already rejected a White House offer to build into the spending bill a dollar-for-dollar match in wall funding and federal health-care payments. Negotiators want the stopgap measure to keep government open by keeping spending flat, including money to keep the ACA going. Trump is hoping to open that up for negotiation in exchange for wall money.

Democrats believe that voters will blame Trump for a shutdown, particularly if congressional leaders omit wall funding from a spending deal. Democrats and GOP leaders appeared to be nearing a spending agreement last week before Trump ramped up his demands.

Aides hailed the budget talks as one of the only active discussions in which Democrats and Republicans maintained common ground. One clear area of agreement was not to include border funding in the stopgap budget. Democrats agreed to include other border-security measures, including money for new drones to patrol the border, but it was agreed that the wall itself should be debated separately, after the government is kept open.

Sen. Marco Rubio (R-Fla.) is among a group of prominent Senate Republicans who have said publicly that they hope to avoid a border wall fight this week.

“I think that’s a fight worth having and a conversation and a debate worth having for 2018,” Rubio said Sunday on CBS’s “Face the Nation.” “If we can do some of that now, that would be great. But we cannot shut down the government right now.

Mulvaney’s hard-line stance is also at odds with a White House faction convinced that a government shutdown would be cataclysmic for an administration already struggling to prove its ability to govern, according to GOP aides in the White House and Congress who spoke on the condition of anonymity to discuss the ongoing talks.

Republican leaders have signaled that they will concentrate this week on keeping the government open, even if that means ignoring White House calls for action on other major priorities, such as rewriting the tax code and overhauling the ACA.

[Ryan promises to keep government open — and makes no promises on health care]

Trump has pushed his staff in recent days to prod House Republicans for final revisions in a health-care proposal that can win support from both the hard-line conservative Freedom Caucus and the moderate Tuesday Group. And that task led advisers over the weekend to rely especially on three key players — Rep. Tom MacArthur (R-N.J.), co-chairman of the Tuesday Group; Rep. Mark Meadows (R-N.C.), chairman of the Freedom Caucus; and Rep. Patrick T. McHenry (R-N.C.), the House GOP chief deputy whip — to finalize legislation.

But the White House’s efforts to work directly with House coalitions and piece together a compromise health-care package have led to private unease on Capitol Hill, where some GOP members close to the leadership have grumbled that Trump aides are setting up the party for defeat or a stumble if support for the tweaked health bill is not as strong as the White House has suggested.

Trump’s advisers, aware of those concerns, still plowed forward Sunday on crafting the bill’s language, citing the president’s desire for action. There were ongoing conversations about the timing for a health vote, with Wednesday, Thursday, Friday or even sometime in early May, if necessary, discussed as options.

Ryan addressed that pressure in a conference call Saturday afternoon, in which he told GOP members that while he hoped that they would continue health-care talks, his top priority will be the stopgap spending bill.

“Wherever we land will be a product the president can and will support.” Ryan said, according to a senior GOP aide on the call.

Abby Phillip and Sean Sullivan contributed to this report.

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