In an exclusive interview with USA TODAY House Democratic Leader Nancy Pelosi accused President Donald Trump of using "scare tactics" to build support for his proposed U.S.-Mexican border wall, which she joked had been reduced from a giant, cement structure "to, I think, a beaded curtain."

Trump and congressional Democrats remained locked in a bitter stalemate Tuesday over billions of dollars in funding for the wall, which Trump said is necessary to end a partial government shutdown heading into its fourth day. Most lawmakers are home for the holiday, so a speedy resolution would amount to a Christmas miracle.

While wishing a Merry Christmas to troops overseas, Trump said he doesn't know when the government shutdown will end.

"It’s a disgrace what’s happening in our country," Trump said in the Oval Office. "But other than that, I wish everybody a very Merry Christmas."

Though congressional Democrats said they will not support money for a border wall, Trump said the United States needs "a wall, a fence, whatever they want to call it." The remarks underscore how dug in both the White House and congressional Democrats have become amid the shutdown that began Friday at midnight.

The president kept a low profile on Christmas Eve, posting on Twitter that he was "alone" at the White House waiting for Democrats to agree to a deal to reopen federal agencies. The White House said Trump met with Homeland Security Secretary Kirstjen Nielsen about border security but provided no details about the discussion.

"At some point the Democrats not wanting to make a deal will cost our Country more money than the Border Wall we are all talking about," Trump posted on Twitter. "Crazy!"

In an interview, Pelosi told USA TODAY over the weekend Trump is "being a fear monger" by asserting immigrants will bring drugs and other dangers into the USA.

Trump ran for president on a promise to strengthen immigration restrictions and build the wall. He took heat from conservatives after the White House initially signaled an openness to a short-term funding measure that would have kept government agencies opened but would not have significantly increased funding border barriers.

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"He talked about terrorists coming in over that particular border, which wasn't so. He talked about people bringing in diseases and all the rest of that, which wasn't so," said Pelosi, D-Calif., who is likely to become speaker after Democrats take over the House of Representatives next month. "He's using scare tactics that are not evidence-based, and it's wrong."

Pelosi mocked the shifting message from the White House about whether Trump wanted a "wall," a fence or some other structure.

"First of all, the fact ... that he says, ‘We're going to build a wall with cement, and Mexico's going to pay for it’ while he's already backed off of the cement – now he's down to, I think, a beaded curtain or something, I'm not sure where he is," Pelosi said.

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A White House spokeswoman did not respond to a request for comment.

As both sides dug in over the shutdown, it was unclear whether any progress was made toward resolving the impasse.

The Senate isn't set to meet again until Thursday at the earliest, and White House officials predicted the shutdown could continue into the new Congress, which will begin Jan. 3. Democrats will take control of the House on that day, and Pelosi said she expects the chamber will pass legislation to reopen federal agencies quickly.

It's unknown whether that measure would include additional money for the border.

"But one thing's for sure, the first week of January, we will be passing legislation to open up government," Pelosi said.

Contributing: Nicole Gaudiano and David Jackson