WASHINGTON — PEN America, an organization representing writers and literary professionals, filed suit against President Donald Trump on Tuesday, claiming he has used regulatory enforcement powers to attack media outlets in violation of the First Amendment.

“He has threatened to engage, and has engaged, in conduct intended to retaliate against specific news organizations and journalists whose content and viewpoints displease him,” the lawsuit stated. “Through his actions, Defendant Trump has intentionally conveyed to all writers and journalists that if he objects to their coverage, they may be subject to retaliation by the federal government.”

Specifically cited are the Justice Department’s decision to challenge the merger of AT&T and Time Warner, in the wake of Trump’s attacks on Time Warner unit CNN.

“While that lawsuit did not succeed in the District Court, the litigation cost CNN’s parent significant resources, including money, time, and opportunity costs,” the lawsuit said. “Those litigation costs continue as the President’s Administration pursues an appeal.”

Another example is Trump’s executive order directing the U.S. Postal Service to examine the shipping rates that it offers companies like Amazon. Trump has called out Jeff Bezos, the company’s founder, as he also owns The Washington Post. Trump has railed against the Post’s coverage of his administration.

“On information and belief, he then personally directed U.S. Postmaster General Megan Brennan to double the rate the Postal Service charges Amazon and other firms to ship packages,” the lawsuit stated. “On October 11, 2018, the Postal Service announced proposed rate increases, including a proposed 12-percent increase for the Parcel Select service used by Amazon.”

Also cited are threats to take away the credentials of White House reporters “whose coverage displeases him and has threatened to challenge NBC’s and other television stations’ broadcast licenses in retaliation for coverage he disliked.”

The lawsuit stated that Trump “has made eminently clear his disdain for the press and the legal protections the First Amendment affords it. He has frequently referred to journalists covering his rallies as ‘disgusting’ and has stated, more generally, that it is ‘frankly disgusting the way the press is able to write whatever they want to write’ and that ‘people should look into that.’”

A White House spokeswoman did not immediately return a request for comment.

The lawsuit seeks a declaration that Trump violated the First Amendment, and an injunction blocking him from using his office to retaliate against speech critical of his administration. PEN America is represented in the case by the nonprofit Protect Democracy and the Yale Law School Media Freedom and Information Access Clinic.