Three journalists have resigned from CNN after the US news network retracted an article alleging a Trump aide was under investigation by Congress.
The story was taken down on Friday following an internal investigation, with an apology to Anthony Scaramucci, an outspoken ally of the president.
Mr Scaramucci said it was not true, accusing the network of attacking President Donald Trump's friends.
Mr Trump responded by taunting CNN in a tweet saying: "FAKE NEWS!"
"Wow, CNN had to retract big story on 'Russia,' with 3 employees forced to resign," he posted on Tuesday morning.
"What about all the other phony stories they do?"
Journalist Thomas Frank, investigative unit editor Eric Lictblau - a Pulitzer Prize winner - and Lex Harris, who oversaw the investigations unit, all resigned on Monday.
'Mistakes'
A spokesman for the network - which earlier said the story "did not meet CNN's editorial standards" - said: "In the aftermath of the retraction of a story published on CNN.com, CNN has accepted the resignations of the employees involved in the story's publication."
The story was written based on the account of a single anonymous source. Many news outlets require at least two sources before running a story.
The president could not resist another dig on Tuesday at the network, tweeting: "Fake News CNN is looking at big management changes now that they got caught falsely pushing their phony Russian stories. Ratings way down!"
CNN - along with organisations like the Washington Post and New York Times - has found itself butting heads with Donald Trump and his administration since they took office.
Mr Trump has often accused the organisation of "fake news" and refused to answer questions put to him by one of its journalists.
But Mr Scaramucci, a Trump transition team member, appeared content with CNN's resolution of the issue.
"@CNN did the right thing. Classy move. Apology accepted. Everyone makes mistakes. Moving on," he tweeted on Saturday.