In an appearance on the BBC’s Question Time, Mr Neil declined to explicitly criticise the new channel, which he officially left on Monday, but said its direction was not the same one envisaged before its launch.
“I had always made it clear that it wouldn’t be a British Fox News and I think you could do something different without going anywhere near Fox,” Mr Neil said.
“Fox deals in untruths, it deals in conspiracy theories and it deals in fake news.
“That’s not my kind of journalism and I would never have set out to do that.”
Mr Neil added: “I’ll let you draw your own conclusions as to why I’m here tonight and not with GB News.”
The veteran journalist also admitted that the channel’s launch could not be thought of as a “startling success” after its opening week was plagued by technical difficulties.
When pressed on whether he had left GB News because it had become too right wing, he said: “People should make up their own minds on that.”
The resignation of Mr Neil, who was the public face of GB News, has been widely seen as a major blow for the channel, just three months after its launch.
The 72-year-old presenter had been on air for less than two weeks before he announced that he would be taking a break from his show.
In a statement earlier this week, Mr Neil suggested that he left the channel because he wanted to “cut back” on his work commitments.
“I am sorry to go but I have concluded it’s time to reduce my commitments on a number of fronts,” he said.
“Over the summer I’ve had time to reflect on my extensive portfolio of interests and decided it was time to cut back.
“I wish GB News well in continuing to fulfil its founding promise and mission to reach audiences currently underserved by existing news broadcasters.”
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