WASHINGTON: US government services will be disrupted until President Donald Trump and Congress agree on a spending deal.

Federal agencies have ordered hundreds of thousands of federal employees not to work, deeming them not essential to protecting people and property.

This shutdown, opens new tab is different from past government closures because Trump has threatened to lay off more federal workers if lawmakers do not pass legislation to avert the closures. His administration had not outlined what cuts to expect as of Wednesday morning.

“We will be looking for opportunities” to reduce the size of the federal government, said White House budget director Russ Vought in a television interview on Tuesday.

Here is a guide to what will stay open and what will close in this government shutdown, according to details federal agencies released so far:

When and why did the government shut down? 

Congress writes detailed spending legislation for most US government agencies each year, but rarely finishes before the fiscal year starts on October 1. Lawmakers typically pass stopgap spending bills to avoid disruption for several weeks or months while they finish their work.

The current stopgap bill expired on September 30. Republicans and Democrats have not reached an agreement on an extension. Wide swaths of the government lack funds to continue their operations.

What happens to social security, medicare and medicaid?  

The Social Security Administration will keep issuing retirement and disability benefits, but will furlough 12% of its staff and pause marketing campaigns, according to the agency’s shutdown plan.

Payments will likewise continue under the Medicare and Medicaid healthcare programs.

Will food aid be continued under SNAP and WIC?

The Supplemental Nutrition Assistance Program, the nation’s largest food aid program, and the Special Supplemental Nutrition Program for Women, Infants and Children, known as WIC, will continue operations during a shutdown as funds allow, according to a shutdown planning document published by the US Department of Agriculture.

Does the mail get delivered? 

The US Postal Service will be unaffected because it does not depend on Congress for funding, USPS said in a statement. Post offices will be open.

What does a shutdown mean for interal revenue service? 

The IRS will be fully staffed for five days, according to agency shutdown plans published Monday.

The strategy does not say what the IRS, which lost about a quarter of its staff this year and now employs about 75,000 people, will do if the shutdown lasts longer than five business days. An agency spokesperson declined to comment.

What about the airports? 

More than 13,000 air traffic controllers will continue working without pay until the shutdown ends, according to the Federal Aviation Administration.

Most TSA employees will continue working, according to an agency statement.

Will federal courts be fully operational? 

The federal judiciary warned that the courts could run out of money to fully sustain operations after Oct. 17.

That is a shift. When the government shut down during Trump’s first term, the courts sustained operations for five weeks.

What does a shutdown mean for the military? 

The 2 million US military personnel will remain at their posts without pay until the shutdown ends, according to a Department of Defense statement.

National Guard forces Trump has deployed to US cities must also continue to work.

Contracts awarded before the shutdown will continue, and the department can place new orders for supplies or services needed to protect national security.

Trump in September ordered the department to rename itself the Department of War, a change that will require action by Congress.

How Does a government shutdown affect law enforcement? 

Agents at the FBI, the Drug Enforcement Administration, Coast Guard and other federal law enforcement agencies will remain on the job.

What happens to borders and homeland security? 

Justice Department staff that administer the immigration court system will largely stay on the job because Trump declared illegal immigration a national emergency, according to a department statement.

Employees that communicate with state and local officials about immigrant arrests will also keep working, according to the statement. Border patrol and immigration enforcement agents will stay at their posts, as would most customs officers, according to the Department of Homeland Security’s shutdown strategy.

Tariff collections will continue, according to the strategy.

Does a shutdown delay key economic data?

Publication, including employment and GDP reports of critical importance to policymakers and investors, will be suspended.

Does a government shutdown affect small businesses?  

The Small Business Administration will furlough 24% of its staff, according to a statement. It will not approve new loans for small businesses to buy equipment and upgrade buildings. Lending to help businesses recover from natural disasters will continue.

What happens if there is a natural disaster? 

The Federal Emergency Management Agency has about $2.3 billion available in its Disaster Relief Fund, according to a September 15 report, meaning the agency should function if a hurricane or other natural disaster strikes. About 4,000 FEMA employees will be furloughed, according to an agency statement.