The Trump administration must halt much of its dramatic downsizing of the federal workforce, a California judge ordered Friday.

Judge Susan Illston in San Francisco issued the emergency order in a lawsuit filed last week by labor unions and cities, one of multiple legal challenges to Republican President Donald Trump’s efforts to shrink the size of a federal government he calls bloated and expensive.

“The Court holds the President likely must request Congressional cooperation to order the changes he seeks, and thus issues a temporary restraining order to pause large-scale reductions in force in the meantime,” Illston wrote in her order.