Thousands of federal employees face the prospect of working without a paycheck as the White House budget office Friday night directed the heads of government departments and agencies to begin implementing shutdown plans.

Funding for nine departments and other agencies lapsed at midnight as President Donald Trump remained in a standoff with Congress, his demand for funding for wall construction along the border with Mexico the sticking point in talks over appropriations and a stopgap funding measure.

“Although we are hopeful that this lapse in appropriations will be of short duration, employees should report to work for their next regularly scheduled tour of duty to undertake orderly shutdown activities,” Office of Management and Budget Director Mick Mulvaney wrote in a memo to department and agency heads as the midnight deadline for funding approached.

“We will issue another memorandum reopening government functions once the President has signed a bill providing for appropriations,” Mulvaney wrote.

Standard shutdown procedure requires only staff performing “essential” duties to report to work, while others would be furloughed until the shutdown ends. Even those who work may not receive their paychecks on time.

Squabbles over Trump’s demand for $5 billion in fiscal 2019 appropriations to pay for a wall along the U.S.-Mexico border wall ended late Friday as the clock ticked toward a shutdown with the midnight expiration of the current stopgap funding.

The replacement bill would extend temporary agency financing through Feb. 8, buying lawmakers some extra time to try to work out the remaining seven fiscal 2019 appropriations bills: Agriculture, Commerce-Justice-Science, Interior-Environment, Financial Services, Homeland Security, State-Foreign Operations and Transportation-HUD.

Overall, nine of 15 federal departments and agencies would be closed if a shutdown wasn’t averted, according to Senate Appropriations Committee ranking member Patrick J. Leahy, D-Vt., who lamented the prospect of “grinding services to the American people to a halt just three days before Christmas.”

According Leahy’s summary, more than 420,000 federal employees would be working without pay during a shutdown that could impact several sectors of the economy, including farmers who depend on the USDA for assistance to local businesses near federal facilities or that depend on the federally backed loans. All the affected agencies have filed contingency plans with the Office of Management and Budget.

Here’s how the shutdown would affect the agencies:

Agriculture

More than 60 percent of the department’s staff would report to work for the first five days of a partial shutdown, but the number of employees at any given agency would vary depending on its mission and funding source, according to the Agriculture Department’s shutdown plans.

At the agency’s Animal and Plant Health Inspection Service, a mix of trust funds and user fees would allow workers to continue to inspect for pests in fruits, vegetables and birds being exported or imported. About 69 percent of employees would continue duties ranging from treatment of ticks in cattle and deer along the U.S.-Mexico border, to caring for animals at labs and research facilities

Carried over funding and reimbursements would allow the Food Safety and Inspection Service to continue inspections of meat, poultry and egg products, lab work to identify food safety threats and emergency preparedness.

About 5 percent of workers at the department’s Food, Nutrition and Consumer Services would be needed to keep benefits flowing to beneficiaries in the Supplemental Nutrition Assistance Program, Women, Infants and Children program and the national school lunch and breakfast programs.

Commerce

With continuing funds from previous appropriations, the department says it will continue to provide services from agencies including the Bureau of the Census, National Institute of Science and Technology and the National Oceanic and Atmospheric Administration.

EPA

The agency will for now continue operating because it still has carried-over funds.

“Prudent management requires the proper preparation for all contingencies, including the possibility that a lapse in appropriated funding could occur,” acting EPA Administrator Andrew Wheeler said in an emailed statement. “EPA’s Contingency Plan for Shutdown calls for the agency to assess whether there are sufficient carryover funds to operate for a period of time in the event of a lapse in funding and a government shutdown. We have done that assessment and determined that EPA has sufficient carryover funds to operate for a limited period of time.”

Financial Regulation

Some, but not all, of the nation’s financial regulatory agencies would be significantly affected. The Office of the Comptroller of the Currency and the Federal Deposit Insurance Corporation would operate normally, as those fee-funded agencies are unaffected by the congressional appropriations process. Similarly, the Consumer Financial Protection Bureau receives its funding from the Federal Reserve and will remain unaffected by a shutdown.

While the Securities and Exchange Commission is also funded through fees, it is subject to the appropriations process and will reduce staffing from 4,400 employees to about 300 essential personnel to handle emergencies and continue law enforcement actions. The SEC’s filing system, EDGAR, will remain accessible, but the Commission will not accept filings, provide interpretative advice or issue no-action letters during the shutdown.

The Commodity Futures Trading Commission and the U.S. Treasury Department will also curtail operations to just a few essential functions such as criminal investigations. Notably, the Tax Cuts and Jobs Act provided the IRS implementation funding through Sept. 30, 2019. Still, only 12.5 percent of IRS employees, mostly related to enforcement, will remain on the job. Representatives from those agencies did not respond to requests for more detail on which functions will remain in operation during the shutdown.

Health and Human Services

Four parts of the Department of Health and Human Services are still running on a continuation of fiscal 2018 funding and would have to initiate shutdown plans if a deal isn’t reached. That includes the FDA and the Indian Health Service, which each have budgets north of $5 billion, and smaller parts of the Centers for Disease Control and Prevention and the National Institutes of Health.

Homeland Security

Most employees at the Department of Homeland Security — 212,500 or 87 percent of staff — are exempt from a lapse in government funding and will be expected to continue to report to work because most of them work in essential services like law enforcement or disaster relief. In other cases, their salaries are funded by money that is not subject to congressional appropriations.

The vast majority of employees at the department’s biggest agencies — including Customs and Border Protection, Immigration and Customs Enforcement, Federal Emergency Management Agency and the Transportation Security Administration — are considered essential personnel, and so continue to work even under a shutdown. Salaries at U.S. Citizenship and Immigration Services are funded by fees paid by visa applicants and immigrant petitioners.

Interior

National parks will remain as accessible as possible “while still following all applicable laws and procedures,” an Interior spokesman said.

There may be some restricted access to National Park Service areas like some public lands, trails and sites because of fewer employees on the ground. The agency said it is prioritizing keeping the most accessible and iconic areas of parks and public lands available to the public, but plans may vary at different locations.

Justice

The Justice Department will largely be up and operating as many of its functions relate to the protection of life and property, which are functions exempt from the shutdown. Altogether, about 84 percent of Justice Department employees are exempt and will be working; that’s 95,000 out of 113,000 Justice Department employees, according to a department memo put out in September of this year.

So the FBI, the Drug Enforcement Agency, the Bureau of Alcohol, Tobacco, Firearms and Explosives, U.S. attorneys, the Bureau of Prisons and department criminal activities go forward during a shutdown. The Office of Special Counsel, under special funding, also goes forward, so Robert Mueller III’s investigative team does not get furloughed.

State

The department’s contingency plan as posted on OMB does not specify operations of offices that will continue, but does say those “identified by the Bureau of Budget and Planning (BP) and the Office of U.S. Foreign Assistance (F) will continue to operate until their respective balances are insufficient to continue.”

Transportation

At the Federal Aviation Administration, services including air traffic control, field inspections and security operations will continue. Indeed, most of the department’s other agencies will continue to operate with carryover funding, according to the DOT contingency plan.

Dean DeChiaro, Ellyn Ferguson, Jim Saksa and Andrew Siddons contributed to this report.Watch: What Really Happens During a Government Shutdown, Explained