Piers Morgan launched a scathing attack on the executive director of Gun Owners of America, calling him an dangerous and an "unbelievably stupid man".
During an interview on his CNN current affairs show, Morgan was questioning Larry Pratt over gun ownership laws in America following the recent Sandy Hook shooting which left 26 people dead, 20 of them children.
During a comparison between the gun crime rate in the US compared to the rest of the world such as the UK and Australia, Pratt said: "America is not the wild west that you are depicting. We only have the problem in our cities and unhappily in our schools where people like you have been able to get laws put on the books that keep people from being able to defend themselves.
"I honestly don't understand why you would rather have people be victims of a crime than be able to defend themselves. It's incomprehensible."
In response, the outspoken former British newspaper editor said: "You're an unbelievably stupid man aren't you?"
Morgan added he believed Pratt was "dangerous man espousing dangerous nonsense" who "doesn't care" about the murder rate in the US.
Morgan also concluded the interview by telling Pratt: "You shame your country".
Pratt, a staunch defender of the Second Amendment, also explained during the interview why he believed teachers should be allowed to have guns in order to protect themselves despite the US already having the largest gun crime rate in the world.
Pratt said: "The problem occurs, sir, in those areas precisely where we have said no guns. The problem doesn't occur where the guns are allowed freely to be carried to be used by people. There we have very low murder rates."
After the show, Morgan took to Twitter, writing: "Still seething after tonight's show. Just can't understand the mentality of those who insist the only answer to #Newtown is MORE guns."
He added: "I don't care if people are upset by my anger and passion re guns. I care about not letting those poor Sandy Hook children die in vain."
An extract of the interview can be seen below: