The Good Morning Britain host labelled Rudy Giuliani "unhinged" after the latter lashed out at Mr Morgan for "misinterpreting on purpose" a recent tweet by the US President concerning the unrest.
Mr Trump said in the post in question, published on May 29, that "when the looting starts, the shooting starts" as protests raged throughout the US over Mr Floyd's death.
Twitter later hid the post behind a warning that it “glorifies violence” while it also emerged the specific phrase Mr Trump used appeared to have origins in the civil rights era.
Clashing over the incident on Thursday, Mr Morgan told Mr Giuliani the US President should "never have said it".
He added: “You’re so wind up in your support for Trump you can’t see the wood from the trees.”
Mr Giuliani hit back, accusing Mr Morgan of being a "failed journalist" and saying: “You misinterpreted him. You’re misinterpreting him on purpose.
“The question is did he know that came from some racist 30 years ago?
“Well, he didn’t know that."
The two men then began shouting over each other, with Mr Morgan calling Mr Giuliani "mad" and "unhinged" over his "abusive" comments, and the latter branding the GMB host a "disgrace" and a "liar".
Footage of the blazing row was subsequently circulated widely on social media.
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