Lawmakers are away from Washington for the holidays and have been told they will get 24 hours' notice before having to return for a vote. And although the Senate is slated to come into session Thursday afternoon, few senators were expected to be around for it.
After a weekend and two holiday days for federal employees, Wednesday was the first regularly scheduled workday affected by the closure of a variety of federal services.
Trump vowed to hold the line on his budget demand, telling reporters during his visit to Iraq on Wednesday that he'll do "whatever it takes" to get money for border security. He declined to say how much he would accept in a deal to end the shutdown.
"You have to have a wall, you have to have protection," he said.
Back from the 29-hour trip to visit U.S. troops, Trump said in a Thursday tweet "we desperately need" a wall on the U.S.-Mexico border, funding for which has been a flashpoint between the White House and Congress ever since Trump took office.
He called on Democrats in Congress to fund his wall, saying the shutdown affects their supporters. He asserted without evidence: "Do the Dems realize that most of the people not getting paid are Democrats?"
Virginia Democratic Sen. Mark Warner called Trump's comments "outrageous." In his tweet, he added: "Federal employees don't go to work wearing red or blue jerseys. They're public servants. And the President is treating them like poker chips at one of his failed casinos."
The shutdown started Saturday when funding lapsed for nine Cabinet-level departments and dozens of agencies. Roughly 420,000 workers were deemed essential and are working unpaid, while an additional 380,000 have been furloughed.
While the White House was talking to congressional Democrats — and staff talks continued on Capitol Hill — negotiations dragged Wednesday, dimming hopes for a swift breakthrough.
Republican Rep. Mark Meadows of North Carolina, a Trump ally who has been involved in the talks, said the president "is very firm in his resolve that we need to secure our border." He told CNN, "If they believe that this president is going to yield on this particular issue, they're misreading him."
The impasse over government funding began last week, when the Senate approved a bipartisan deal keeping government open into February. That bill provided $1.3 billion for border security projects but not money for the wall. At Trump's urging, the House approved that package and inserted the $5.7 billion he had requested.
But Senate Republicans lacked the votes they needed to force the measure through their chamber. That jump-started negotiations between Congress and the White House, but the deadline came and went without a deal.
The shutdown has been playing out against the backdrop of turmoil in the stock market.
Kevin Hassett, the chairman of the White House's Council of Economic Advisers, said the shutdown does not change the administration's expectation for strong growth heading into 2019. He told reporters a shutdown of a few weeks is not going to have any "significant effect on the outlook."
Among those affected by the shutdown — the third of 2018 — are the departments of Homeland Security, Transportation, Interior, Agriculture, State and Justice. Those being furloughed include 52,000 workers at the Internal Revenue Service and nearly everyone at NASA. About 8 in 10 employees of the National Park Service are staying home, and many parks have closed.
The shutdown didn't stop people from visiting the White Sands National Monument in southern New Mexico, where hundreds of unauthorized visitors have in recent days climbed over a fence to enter the monument, according to The Alamogordo Daily News. State highway workers were sent to the area Monday to erect "no parking" signs along U.S. 70 outside the monument.
Trump has claimed federal workers are behind him in the shutdown fight, saying many told him, "stay out until you get the funding for the wall.'" He didn't say who told him that. Many workers have gone to social media with stories of the financial hardship they expect to face because of the shutdown.
One union representing federal workers slammed Trump's claim. Paul Shearon, president of the International Federation of Professional and Technical Engineers, said the union has not heard from a single member who supports Trump's position.
"Most view this as an act of ineptitude," he said.
Superville reported from al-Asad Air Base in Iraq. Associated Press writers Zeke Miller in Washington and Paul Davenport in Alamogordo, New Mexico, contributed to this report.