A federal judge has indefinitely blocked President Donald Trump’s plan to lay off thousands of federal workers during the ongoing government shutdown — a sweeping decision that marks a significant setback for the administration’s efforts to cut the federal workforce.

U.S. District Judge Susan Illston, appointed by former President Bill Clinton, issued the injunction late Tuesday, siding with unions that argued the mass layoffs violated federal employment protections. The ruling freezes the administration’s “reductions in force” order while a broader legal challenge moves forward in court.

According to court filings, more than 4,000 government employees were slated to lose their jobs under the plan. Illston, who had earlier placed a temporary hold on the layoffs, said she believes the firings likely exceed the President’s legal authority.

“This order is positive for the American people and a major blow to the Trump-Vance administration’s unlawful attempt to make the Project 2025 playbook a reality by targeting our nation’s career public servants, who work for all Americans,” said Skye Perryman, president of Democracy Forward, which represents two of the unions involved in the case.

The American Federation of Government Employees (AFGE), representing over 700,000 federal workers, praised the court’s action and renewed calls for Congress to end the shutdown. “Both political parties have made their point, and still there is no clear end in sight,” AFGE National President Everett Kelly said, urging lawmakers to pass a clean spending bill.

The American Federation of State, County and Municipal Employees (AFSCME), another union in the lawsuit, described the court’s ruling as a “victory for federal workers and ongoing efforts to protect their jobs from an administration hellbent on illegally firing them.” AFSCME President Lee Saunders added, “Unlike the billionaires in this administration, public service workers dedicate themselves to serving their communities. These attempted mass firings would devastate both the workers and the people they serve.”

The Trump administration, however, has shown no indication of backing down. Office of Management and Budget Director Russell Vought recently warned that as many as 10,000 federal employees could ultimately face termination if the shutdown continues.

While the White House referred inquiries to the OMB — which did not immediately respond — the Justice Department has refrained from defending the layoffs, arguing that personnel disputes should be handled through the Merit Systems Protection Board rather than the courts.

Senate Democrats have meanwhile rejected multiple House attempts to reopen the government, voting down a Republican-backed funding bill for the 13th time on Tuesday.

Legal experts say Judge Illston’s decision could signal broader judicial skepticism toward executive overreach during fiscal emergencies. The ruling, they note, not only safeguards thousands of federal jobs but could also constrain the administration’s future attempts to reshape the civil service during political standoffs.