Watch: Piers Morgan lash out at Meghan Markle in Fox News interview
Morgan said in his own 'tell-all interview' with US channel Fox News: "You know I knew Princess Diana well. I think she would be horrified by the split between Harry and his brother.
“She would be horrified by the schism now between Harry and the Royal Family generally and by the appalling smearing of the Queen which is already causing damage in some of the Commonwealth countries.”
He also attacked Prince Harry's claims he has been financially cut-off by the Royal Family since he and Meghan made the decision to quit their royal duties and move to the US.
Morgan said: “What’s happened to that guy? He’s turned into this whiny brat.
“In his mid-30s, complaining that his dad isn’t still financing everything that he does. Complaining that he was cut off by daddy and his millions.
“Actually that wasn't true either - It turns out Prince Charles had carried on financing him. And remember Harry inherited millions when his mother died."
The former tabloid editor – who met with Princess Diana in his role as a journalist several times before her death in 1997 – left breakfast show GMB after saying he "didn't believe a word" of Meghan's claims in her tell-all interview with Oprah.
Morgan's accusations the Duchess of Sussex was lying prompted thousands of complaints from viewers and broadcasting regulator Ofcom has launched an investigation.
The TV host has now challenged Markle to name the members of the Royal Family she has accused of telling her not to seek help when she felt suicidal, and who questioned what skin colour her son Archie would have.
Morgan said: "You're accusing two people in the palace of being unspeakably cruel simply to protect the brand of the Royal Family, if that is true let's have the names of these people and let's go to them and ask them is this true.
"'Did you tell a suicidal woman, who told you she was suicidal, not to get help?' - because I find that impossible to believe."
He also said the duchess was, "accusing the Queen and the Monarchy and the institution as being racist – that's really what was going down here."
Morgan claimed the question may have been as "innocent" as somebody saying "given Meghan's father is white, her mother's black, what colour would the baby be?"
He added it had been, "loaded with a sense of derogatory tone or concern, then it becomes racism".
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