Politicians reportedly met a Yale University psychiatry professor last month to discuss Donald Trump’s leadership ability and behaviour.
Dr Bandy Lee spoke to more than a dozen members of Congress on 5 and 6 December, all of whom were Democrats with the exception of one Republican Senator, according to Politico.
“We feel that the rush of tweeting is an indication of his falling apart under stress. Trump is going to get worse and will become uncontainable with the pressures of the presidency,” Dr Lee told the magazine.
She reportedly highlighted the President “going back to conspiracy theories, denying things he has admitted before, his being drawn to violent videos”.
Dr Lee is the editor of “The Dangerous Case of Donald Trump”, in which 27 psychologists, psychiatrists and mental health professionals assess the President’s level of “dangerousness”.
“North Korean Leader Kim Jong Un just stated that the ‘Nuclear Button is on his desk at all times.’ Will someone from his depleted and food starved regime please inform him that I too have a Nuclear Button, but it is a much bigger & more powerful one than his, and my Button works!” Mr Trump wrote on Twitter.
Mr Trump also posted a series of erratic tweets taking credit for a lack of plane crashes and announcing the "corrupt media awards".
The US President has repeatedly taunted North Korea and its leadership and threatened to punish the state’s testing of intercontinental ballistic missiles with a military response.
Last year, Mr Trump referred to Kim Jong-un as “Little Rocket Man”, leading to the North Korean leader to fire back that the US President was a “mentally deranged US dotard” who needed to be attacked “with fire”.
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