- Employees such as prison guards, airport staff and FBI agents have been working without pay.
- President Donald Trump is refusing to approve a federal budget unless it includes funding for a border wall.
- The House and Senate overwhelmingly passed a bill on Friday to ensure all government workers receive retroactive pay after the shutdown ends.
- Trump has been threatening to declare a national emergency, which would allow him to bypass Congress and build the wall by raiding military budgets.
Hundreds of thousands of US government workers have missed their first payday of the year as the partial shutdown of federal agencies bites deeper.
Employees such as prison guards, airport staff and FBI agents have been working without pay.
The government shutdown, which began last month, will become the longest in history on Saturday on its 22nd day.
President Donald Trump is refusing to approve a federal budget unless it includes funding for a border wall.
But Democrats have rejected his request for $5.7 billion (£4.5 billion).
About a quarter of the federal government is out of operation until a spending plan is agreed, leaving 800,000 employees unpaid.
On Friday, those workers missed their first payday of this shutdown. Some shared their blank payslips on social media.
Oscar Murillo, an aerospace engineer at Nasa, posted his $0 cheque on Twitter and said he had actually lost money because of mandatory deductions.
Another Twitter user, Cat Heifner, shared what she said was her brother's payslip, showing he had been paid one cent for his work as an air traffic controller.
Meanwhile, the classified advertising website Craigslist has been flooded with listings from federal workers trying to sell their possessions.
Items ranging from beds to old toys have been listed as "government shutdown specials".
"Sells for $93.88 at Walmart. Asking $10," one advert for a child's rocking chair reads. "We need money to pay bills."
A food bank in Washington, DC reported an influx of federal workers.
Radha Muthiah, head of Capital Area Food Bank, said that dozens of volunteers are working to pack bags of food for affected staff.