Donald Trump’s latest executive order has unions up in arms — again.

Trump signed an executive order on Thursday ending collective bargaining for tens of thousands of federal employees, including those who work in border security, energy, and public safety.

It does not include traditional law enforcement.

At a news conference on Capitol Hill on Friday, the president of the nation’s largest union, supporting 800,000 federal employees, lashed out at Trump.

“They are taking this action because AFGE is standing up for our members,” said Everett Kelley, president of the American Federation of Government Employees. “But I want to assure everybody that AFGE will always stand up for its members.”

Also attending the news conference were Maryland Reps. Steny Hoyer and Jamie Raskin.

“This is the retaliation. This is the revenge. This is the shut ’em up effort,” said Hoyer, adding the actions are “consistent with the Republican Party’s long-standing hostility for the rights of working men and women to organize.”

“Federal law gives federal employees the right to engage in collective bargaining,” said Raskin, adding, “That’s how these unions were formed.”

He said this will be a win for labor when it inevitably moves into the courts.

“An executive order is just an order from the president to his staff,” Raskin said. “And he thinks that it trumps federal law and that it trumps the constitution, and it doesn’t.”