Time is running out for the US Congress to pass a funding bill to keep the federal government functioning.
If nothing is agreed to by Saturday, Washington will run out of money to keep the federal government fully operational.
So far, there is little sign Congress will act in time to prevent a shutdown, as a dispute between far-right Republicans and other politicians drags on.
Viewed from overseas, a US federal shutdown might merely look like a domestic problem created by polarised politicians. But a closure of key federal services could have impacts abroad, too.
What will happen to visa applications?
Under the US State Department's shutdown plan, all embassies and consulates would remain open for national security reasons.
Passport and visa processing would continue as long as there are sufficient fees to cover operations. Non-essential official travel, speeches and other events would be curtailed.
Some foreign aid programmes could run out of money as well.
What about travel to the US?
In the event of a government shutdown, airport security screeners and air-traffic control workers would be required to work, according to recent contingency plans, though absenteeism could be a problem.
Some airports had to suspend operations during a shutdown in 2019 when air traffic controllers called in sick, so there is a risk flights to the US could be subject to delays or cancellations.
Training for new air traffic controllers would stop, which Transport Secretary Pete Buttigieg has warned could worsen a shortage of qualified workers.
Can packages still be sent to the US?
The US Postal Service would be unaffected as it does not depend on Congress for funding.
Will the US military be affected?
Two million US military personnel would remain at their posts, but roughly half of the Pentagon's 800,000 civilian employees would be furloughed.
Contracts awarded before the shutdown would continue, and the Pentagon could place new orders for supplies or services needed to protect national security.
Other new contracts, including renewals or extensions, would not be awarded, Reuters reported.
Payments to defence contractors such as Boeing, Lockheed Martin and RTX – formerly known as Raytheon – could be delayed.
How will the stock market react?
US government shutdowns can unleash short-term volatility but overall, they have not historically had much impact on financial markets.
However, a shutdown could affect the nation's credit rating, which took a hit following the debt ceiling stand-off earlier this year.