CNN, MS NOW and Politico have said they have notified Donald Trump's administration that they are filing a lawsuit over being denied White House access.
Reporters from the three major news outlets were blocked from the White House on Saturday, a day after Mr Trump said he was banning them because of reporting what he called "fake news".
"Without notice or process, the White House revoked our journalists' credentials because it objected to our reporting," the publications said in a joint statement on X on Monday.
"Left unchallenged, this threatens press freedom and the public's right to independent journalism free from government interference."
All three news outlets had hinted at legal action, saying they would vigorously defend their First Amendment rights.
White House reporters from the two cable networks - Betsy Klein of CNN and Akayla Gardner of MS NOW - went live to report they had been turned away, and had their press badges deactivated when arriving for their jobs at the White House.
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Shortly afterwards, Politico said its White House reporter Cheyenne Haslett was also denied access and had her badge taken away.
In his second term, Mr Trump and his Republican administration have punished certain media outlets, both in the courtroom and through regulatory action.
The US president has also criticised individual reporters in person or over social media, sometimes insulting them in media briefings, or in his recent speech at the White House Correspondents' Association dinner.
The WHCA's president, Jacqui Heinrich, called on the Trump administration to immediately restore the three outlets' access.
"The implications extend beyond these organisations: a standard used to exclude one news outlet because of its coverage could be applied to any outlet in the future," Ms Heinrich said.
"The American people, through a free and independent press, must be able to scrutinise those elected to power, regardless of whether government officials view it favourably."
(c) Sky News 2026: CNN, MS NOW and Politico 'to sue' over White House ban

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