US President Donald Trump.
The US government shutdown is poised to become the longest ever this week.
Entering its 34th day on Monday, it is only one day short of the 35-day record set by the 2018-2019 closure under President Donald Trump's first administration.
Showing no sign of backing down, Trump said he "won't be extorted" by Democrats to extend subsidies for the expiring Affordable Care Act before they agree to reopen the government.
"It's going to get solved. Eventually, they're going to have to vote," said Trump in an interview with CBS' "60 Minutes" on Sunday.
"And if they don't vote, it's their problem."
The shutdown, which began on Oct 1 after Democrats and Republicans failed to agree on a funding bill, has caused widespread disruptions.
Thousands of federal workers, including air traffic controllers, are set to miss additional paychecks.
According to Airlines for America, a trade association for leading US airlines, more than 3.2 million passengers have had flights delayed or canceled due to air traffic controller shortages since the shutdown began on Oct. 1, Reuters reported.
The shutdown has forced 13,000 air traffic controllers and 50,000 Transportation Security Administration officers to work without pay and disrupted tens of thousands of flights, Reuters added.
Transportation Secretary Sean Duffy told CNBC on Monday that officials would shut down the whole airspace "if we thought that it was unsafe."
"America's travel economy has already lost more than 4 billion US dollars due to the shutdown," the US Travel Association, along with hundreds of other travel-related groups and companies, told lawmakers in a letter on Monday.
"With Thanksgiving, the busiest travel period of the year, imminently approaching, the consequences of a continued shutdown will be immediate, deeply felt by millions of American travelers, and economically devastating to communities in every state," the letter said, urging Congress to immediately pass a clean continuing resolution to reopen the federal government.
According to a report by the Congressional Budget Office last week, the ongoing shutdown could cost the US economy between 7 billion and 14 billion dollars, depending on how long it drags on.
Also in the crossfire are the 42 million Americans who rely on federal food aid.
House Democratic Leader Hakeem Jeffries has accused the Trump administration and Republicans of threatening to "weaponise hunger" against the American people and withholding funding for nutritional assistance for children, seniors, veterans and women.
The Trump administration said Monday that it will partially fund the Supplemental Nutrition Assistance Program (SNAP) for November, after two judges issued rulings requiring the government to keep the nation's largest food aid program running.
The US Department of Agriculture said in a court filing on Monday that a total of 4.65 billion dollars in a contingency fund will be used for November SNAP benefits, which could cover 50 percent of eligible households' current allotments.
Senate Democrats have voted 13 times against a GOP-led stopgap bill to fund the government until Nov 21, insisting that Trump and Republicans must negotiate with them first.
Senate Majority Leader John Thune on Monday told reporters that he was "optimistic" about reopening the government this week.
"Based on, sort of, my gut of how these things operate, I think we're getting close to an off-ramp here."But he also added, "If we don't start seeing some progress or some evidence of that by at least the middle of this week, it's hard to see how we would finish anything by the end of the week."
The longest government shutdown in U.S. history occurred under Trump's first administration, lasting 35 days from Dec 22, 2018 to Jan 25, 2019, as Democrats refused to back Trump's proposed funding for the US-Mexico border wall.
The Congressional Budget Office's analysis found that the record shutdown cost the U.S. economy 3 billion dollars in forgone economic activity that was never recovered.
