US President Donald Trump has said he would like to abolish the agency.

A United States federal judge has ruled the Trump administration acted unlawfully by ordering job cuts at the federal agency in charge of responding to the country’s natural disasters.

On Friday, US District Judge Susan Illston in California said the US Department of Homeland Security (DHS), which oversees the Federal Emergency Management Agency (FEMA), exceeded its authority when it ordered personnel changes that effectively stripped the emergency agency of control over its own workforce.

The ruling centres on thousands of temporary FEMA reservists who are called upon to help communities after hurricanes, wildfires, floods and other disasters.

Labor groups representing federal workers sued to block the administration’s decision to stop renewing many of those contracts.

After Hurricane Katrina battered parts of the US Gulf Coast in 2005, the US Congress strengthened FEMA’s independence. US federal law says DHS cannot substantially or significantly reduce the agency’s authority, responsibilities or functions.

Illston, who was appointed by former US President Bill Clinton, said the Trump administration had failed to provide what she described as a “reasoned” explanation for its decision to restrict FEMA’s ability to renew contracts. She also noted FEMA was projecting a workforce of 11,383 employees for the coming fiscal year — about half of its previous level — without a clear justification for the figure.

The dispute comes amid a broader effort by US President Donald Trump’s administration to reduce the size of the federal workforce. Trump has previously questioned the need for FEMA and suggested that states, not the federal government, should assume greater responsibility for disaster preparedness.

The ruling did not immediately order the administration to reverse the cuts or impose penalties. Illston said those issues would be considered in a separate decision expected next month.