The top American television networks suspended on Monday their involvement in a rotation of broadcasters covering President Donald Trump, as three leading outlets filed a lawsuit after being banned from the White House last week.
Broadcasters CNN and MS NOW, along with news outlet Politico, filed suit after Trump last week ordered them to be barred from the presidential complex.
"This ban could not be a more direct assault on the First Amendment nor a more blatant violation of our most fundamental constitutional principles," the organizations said in a court filing.
Shortly afterward, the five major U.S. broadcasters said they were halting "pool" coverage of the White House in solidarity with CNN.
CNN had been scheduled to serve Monday as the White House TV pool, a rotating assignment in which a broadcaster films on behalf of all television outlets for the day.
"The public has a vital interest in receiving accurate, independent information about its government. No administration should restrict a news organization because it objects to its reporting," ABC, CBS, CNN, Fox and NBC said in a statement.
The boycott means there will be no pooled coverage of Trump's travel to the U.N. General Assembly in New York on Monday, where he is due to meet a series of world leaders.
Trump was unrepentant, with the 80-year-old Republican branding the media a "cancer" and a threat to national security.
"The White House is not instituting an assault on the Free Press, something which I cherish," Trump said on his Truth Social network.
"It is instituting an assault on the FAKE NEWS, something that has grown like Cancer in our beloved United States of America."
'Threatens press freedom'
Trump announced the ban on Friday in a major escalation of his years-long assault on the U.S. media, especially on outlets that report critically on him and his administration.
Journalists from CNN, MS NOW and Politico were denied access to the White House grounds on Saturday and had their passes confiscated.
The outlets said the White House revoked their journalists' credentials "without notice or process" because it "objected to our reporting."
"Left unchallenged, this threatens press freedom and the public's right to independent journalism free from government interference," they said in their joint statement.
Their lawsuit calls for the immediate overturning of the ban and a ruling that it violates the First Amendment of the U.S. Constitution, which upholds the right to free speech.
Trump has not detailed what prompted the ban, but said in response to a question from an Agence France-Presse (AFP) reporter in the Oval Office on Friday that it was "really just cumulative stories over the last two years."
"They want to try and diminish the Republicans and a Republican administration," Trump added.
Trump warned Friday that other outlets could face a similar fate, without saying which.
The billionaire former reality TV star has long attacked media outlets that have aired critical coverage of his campaigns and administrations, repeatedly blasting the press as the "enemy of the people."
Through both terms in the office, he has claimed journalists have failed to show sufficient appreciation for his accomplishments. Trump has also stood out in presidential history for routinely insulting journalists he doesn't like, both in person and on social media.