Fox News has notified Tucker Carlson’s legal team the former prime-time host violated his contract with the network when he launched his own Twitter show, Axios reports, citing a copy of a letter obtained by the news website.

Carlson released the first episode of his new show on Twitter on Tuesday, weeks after being taken off the air by Fox following a damaging defamation lawsuit over false claims of election fraud.

Fox News general counsel Bernard Gugar sent a letter to Carlson’s legal team saying Carlson “is in breach” of his contract agreement after he posted a clip of his new show on Twitter on Tuesday evening, according to Axios.

Reuters could not immediately reach Carlson’s legal team for comment.

His lawyer told Axios any legal action by Fox would violate his First Amendment rights to free speech guaranteed by the US Constitution.

“Fox defends its very existence on freedom of speech grounds,” Carlson’s lawyer, Bryan Freedman, said in a statement cited by Axios.

“Now they want to take Tucker Carlson’s right to speak freely away from him because he took to social media to share his thoughts on current events.”

Fox News did not immediately respond to a request for comment.

The letter quoted by Axios refers to Carlson’s contract, and said its former prime time star was “prohibited from rendering services of any type whatsoever, whether ‘over the internet via streaming or similar distribution, or other digital distribution whether now known or hereafter devised’.”

– AAP