President Trump took aim at collective bargaining for federal employees in certain agencies with an executive order he signed Thursday.

The order, which was taken to “enhance the national security” of the U.S., applies to numerous agencies and their subdivisions, including the departments of State, Defense, Justice, Health and Human Services, Commerce, Veterans Affairs and Energy, plus parts of Homeland Security.

“President Trump is taking action to ensure that agencies vital to national security can execute their missions without delay and protect the American people,” a fact sheet put out by the White House said. “The President needs a responsive and accountable civil service to protect our national security.”

The order argues that the Civil Service Reform Act of 1978 lets the president take such measures.

“President Trump refuses to let union obstruction interfere with his efforts to protect Americans and our national interests,” the fact sheet said.

It noted that Veterans Affairs’ “unions have filed 70 national and local grievances over President Trump’s policies since the inauguration — an average of over one a day.”

American Federation of Government Employees National President Everett Kelley condemned the executive order and said the group is “preparing immediate legal action and will fight relentlessly to protect our rights, our members and all working Americans from these unprecedented attacks.”

He added, “President Trump’s latest executive order is a disgraceful and retaliatory attack on the rights of hundreds of thousands of patriotic American civil servants — nearly one-third of whom are veterans — simply because they are members of a union that stands up to his harmful policies.”

The American Federation of Labor and Congress of Industrial Organizations also bashed the order, saying it “strips the fundamental right to unionize and collectively bargain.”

“It’s clear that this order is punishment for unions who are leading the fight against the administration’s illegal actions in court — and a blatant attempt to silence us,” AFL-CIO President Liz Shuler said in a statement.

She said her union will fight the order.

Since his first day in office, Mr. Trump has been at war with the federal workforce. He demanded that any federal workers working from home to return to their offices and directed his Department of Government Efficiency to check on such employees and cut agencies’ workforce.

An executive order from last month directed DOGE to work with agency heads to “shrink the size of the federal workforce and limit hiring to essential positions.”

“Agencies will undertake plans for large-scale reductions in force and determine which agency components (or agencies themselves) may be eliminated or combined because their functions aren’t required by law,” the order fact sheet said.

The Department of Homeland Security ended collective bargaining with the Transportation Security Administration.

The TSA’s union called the action an “unprovoked attack,” but the agency said the action would “ensure Americans will have a more effective and modernized workforce across the nation’s transportation networks.”