President Donald Trump said that should Congress not agree to fund his wall, he will allow the government to close again or declare a "national emergency"

President Trump's New Vow on His Border Wall: Give It to Me or the Government Could Shut Down Again in 3 Weeks

Even as he announced Friday he would agree to temporarily reopen the federal government after a 35-day shutdown, President Donald Trump said he was not abandoning his signature proposal to build a border wall with Mexico.

Just the opposite, he vowed.

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Trump said that should Congress not agree to fund a wall, he will allow the government to close again or — wading into legally questionable territory — declare a “national emergency” and attempt to allocate the funds himself without approval.

“We really have no choice but to build a powerful wall or steel barrier,” he told reporters from the White House’s Rose Garden. “If we don’t get a fair deal from Congress, the government will either shutdown on Feb. 15 again or I will use the powers afforded to me under the laws and the Constitution of the United States to address this emergency. We will have great security.”

The president was reversing himself in agreeing to spending bills without a guarantee of a southern wall, which has been a signal issue of him dating back to his campaign. (With his assent on Friday, both houses of Congress were expected to move imminently to pass spending bills which Trump said would include backpay for affected workers. )

In his speech announcing the shutdown would end, Trump also took pains not to distance himself from the idea of a wall — reiterating his familiar arguments about the perils of illegal immigration and the value of borders secured his way.

Trump said that in the three weeks that the government would reopen, a bipartisan group of lawmakers would work with homeland security experts on a bill funding border security and related measures including, he hoped, a wall.

“Barriers, fences or walls, or whatever you want to call it will be an important part of the solution,” he said.

Image zoom President Donald Trump Michael Candelori/REX/Shutterstock

Over the next 21 days, I expect that both Democrat and Republicans will operate in good faith,” Trump continued. “This is an opportunity for all parties to work together for the benefit of our whole beautiful wonderful nation. If we make a fair deal, the American people will be proud of their government for proving that we can put country over party.”

Such confidence is likely to be undercut by the starker reality on Capitol Hill: Democrats won decisively in the midterm elections, sweeping their majority to power in the House where they believe they were elected to act as a check on the president.

Nancy Pelosi, the House speaker, has dismissed a border wall as “immoral” and “ineffective.” At the same time Democrats have agreed to work with Republicans on broad funding for border security — though, should such a compromise result in a bill without a wall, the country is now poised to repeat itself.

Speaking with PEOPLE earlier this month, amid the month-long shutdown, Wisconsin newlywed Mallory Lorge said she had been forced to ration the insulin used to treat her diabetes because she could no longer afford the $300 co-pay for a new supply.

Lorge, 31, had been on sick leave from the Department of the Interior before the government closed on Dec. 22.

“I am so scared of more bills,” she told PEOPLE. “The stack on my table is a couple inches high.”