President Trump signed a bill late Friday to fund the U.S. government for three weeks, ending, at least temporarily, the longest government shutdown in U.S. history.

The 35-day partial government shutdown will temporarily end as Trump agreed to a resolution to reopen the government until Feb. 15 and leave current funding levels unchanged with no additional money for a wall along the U.S.-Mexico border.

The debate over border security will continue while the resolution is in place, but the move is designed to take the stress off the system and assure that some 800,000 federal workers get paid.

But by Saturday, the president already warned in a Twitter post that "21 days goes very quickly" and that it will "not be easy to make a deal."

"I think the President wants his $5.7 billion," Mick Mulvaney, the director of the Office of Management and Budget, told Fox News Sunday, when asked if the Trump would take less than that amount for a wall while negotiations on border security continue. Mulvaney implied the same day on CBS News' Face The Nation that Trump would consider shutting down the government over the fight for wall cash.

Those comments follow remarks in the White House Rose Garden Friday, when Trump said Federal employees will get their back pay as soon as possible.

Hours later, as Democrats claimed victory and ardent Trump supporters said he had caved, Trump tweeted: 

White House Press Secretary Sarah Huckabee-Sanders retweeted Trump, saying that he would move ahead with building a wall in 21 days regardless of the outcome of any discussions between the White House and Congress. 

The settlement between the White House and congressional leaders came as traffic at major airports in the Northeast was significantly delayed on Friday because of concerns about the air traffic control system related to absent workers affected by the shutdown. Economists from both Bank of America and Barclays Research wrote Friday in reports that the longest government shutdown in history is already weighing on the national growth rate in gross domestic product. Bank of America slashed its forecast for first-quarter GDP by 0.2 percentage point to an annual rate of 2%, according to the report.

The resolution of the stand-off does not include extra money for Trump's signature campaign issue, the building of a wall on the Mexican border. Instead, the agreement leaves unchanged the sum of money already agreed to by Democrats for border security.

The Federal Aviation Administration lifted a halt to arriving flights into New York's LaGuardia airport after air traffic control staffing issues from the government shutdown forced the temporary closure.

The halt stemmed from a shortage of workers at an air traffic control center in Washington. Flights at Washington's Reagan National, Newark's Liberty International and Philadelphia's International airport also were delayed on Friday.

Two competing Senate bills to reopen the government failed on Thursday.

The Senate and House both approved the continuing resolution to restore government funding Friday afternoon.