Incoming Trump Chief of Staff Mick Mulvaney said during a television interview Sunday that the President wouldn’t abandon his push for border wall funding and that is “very possible” that the current government shutdown could run into the new year.

Trump had promised on the 2016 campaign trail that he would get Mexico to pay for the wall separating both countries. Mexico has repeatedly said it will not foot the bill. Trump’s present refusal to sign a budget that doesn’t include $5 billion in funding for a border wall propelled the country into a partial shutdown of the federal government at midnight Saturday.

On Fox News Sunday, Mulvaney said Trump back down from his “fight over border security,” also saying “I don't think things are going to move very quickly.”

Mulvaney also stated “there's a chance this could go into the next Congress,” which starts on Jan. 3.

Mulvaney, Trump’s Office of Management and Budget director, also told ABC News Chief White House Correspondent Jonathan Karl on Sunday that money for a border wall must come from the Treasury Department, explaining “the Department of Homeland Security can't actually spend money from Mexico.”

“Technically, you and I both know that it cannot work exactly like that,” Mulvaney also said when pushed on Trump’s campaign promise. “The department of Homeland Security can't actually spend money from Mexico. We have to get it from the treasury.”

Mulvaney said that he and Vice President Mike Pence met with top Congressional Democrats and Republicans to discuss shutdown negotiations on Saturday.

"We gave them an offer late yesterday afternoon and we're waiting to hear back," Mulvaney said.

But Congress has already adjourned for the winter holidays. Senate Majority Leader Mitch McConnell said he would be willing to reconvene the chamber before it's back in session on Thursday should a deal be struck. House Majority Whip Steve Scalise, however, told ABC News that a vote would not be held before Thursday.

Muvlaney also told ABC that Trump wouldn’t back down from his snap decision to pull American troops from Syria, which spurred the resignations of two top U.S. defense officials. Trump announced on Wednesday that the fight against ISIS was over and that he would withdraw 2000 U.S. soldiers from Syria.

Brett McGurk, the leading diplomat who negotiated and headed the international coalition to fight ISIS, quit Friday in protest of Trump’s abrupt declaration. McGurk’s resignation, which came some two months before his expected departure, came several days after Defense Secretary Gen. James Mattis also quit in opposition of Trump’s move.

“Is there any chance the president changes his mind about this and reverses course?” Karl asked.

“No, I think the president has told people from the very beginning that he doesn't want us to stay in Syria forever,” Mulvaney replied. “You're seeing the end result now of two years worth of work.”

While Mulvaney’s tour of the talk show circuit was ostensibly to tout Trump’s policies, he also downplayed speculation that Trump had already turned on him.

Trump’s rumored disfavor reportedly stemmed from a two-year-old video uncovered by the Daily Beast in which Mulvaney calls him a “a terrible human being.”

“Yes, I am supporting Donald Trump, but I’m doing so despite the fact that I think he’s a terrible human being,” Mulvaney was recorded saying one week before the 2016 election.

“We joked about it,” Mulvaney said of the video during his ABC appearance. “What's wrong with Washington, D.C.? People spend a lot more time looking at what people say instead of what they do.”