ATLANTA (CNN) —   President Donald Trump called North Korean leader Kim Jong Un a “madman” Friday morning, the latest escalation in their combative rhetoric.

“Kim Jong Un of North Korea, who is obviously a madman who doesn’t mind starving or killing his people, will be tested like never before!” Trump wrote in an early morning tweet.

The threatening message came hours after the rogue nation’s foreign minister said that North Korea could test a powerful nuclear weapon over the Pacific Ocean in response to Trump’s threats of military action.

Ri Yong Ho spoke to reporters in New York shortly after Kim made an unprecedented televised statement, accusing Trump of being “mentally deranged.”

On Tuesday, Trump threatened to “totally destroy” North Korea in a speech to the UN General Assembly if it moves against the US or its allies.

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