A federal judge Thursday refused a group of government employee unions’ request to block the Trump administration from moving ahead with plans to dramatically reduce the federal workforce.

U.S. District Judge Christopher Cooper ruled that federal law mandates the unions bring their challenge before the Federal Labor Relations Authority (FLRA), which adjudicates labor relations within the federal bureaucracy, rather than a federal district court.

The decision notches another victory for Trump’s Justice Department, which is defending against dozens of lawsuits challenging a broad range of the president’s executive actions, including the administration’s efforts to slash spending and reshape government agencies.

“The first month of President Trump’s second administration has been defined by an onslaught of executive actions that have caused, some say by design, disruption and even chaos in widespread quarters of American society,” wrote Cooper, an appointee of former President Obama.

“Affected citizens and their advocates have challenged many of these actions on an emergency basis in this Court and others across the country,” he continued. “Certain of the President’s actions have been temporarily halted; others have been permitted to proceed, at least for the time being. These mixed results should surprise no one.”

The unions’ lawsuit challenged mass terminations of probationary employees, the administration’s plans for additional mass layoffs, known as a reduction in force (RIF), and its offer for most federal employees to accept a buyout.

Another federal judge previously rejected an attempt to block the buyouts in a separate lawsuit, but litigation against the probationary employee firings remains ongoing after a coalition of unions filed yet another lawsuit Thursday.

The case at hand was brought by the National Treasury Employees Union (NTEU), the National Federation of Federal Employees, the International Association of Machinists and Aerospace Workers, the International Federation of Professional & Technical Engineers and United Auto Workers.

The unions argued that the administration’s plans violates the separation of powers and regulations for how the federal government can carry out RIFs.

Cooper took no position on those issues, instead ruling that the unions brought their challenge in the wrong forum.

“The Court acknowledges that district court review of these sweeping executive actions may be more expedient. But NTEU provides no reason why it could not seek relief from the FLRA on behalf of a class of plaintiffs and admits that it would ask other agencies to follow an administrative judge’s ruling in its favor,” Cooper wrote.

Trump fired the FLRA’s Democratic-appointed chair, Susan Grundmann, earlier this month, but she is fighting her termination in court

Updated 5:30 p.m.