North Korean leader Kim Jong Un responded to President Donald Trump's speech before the United Nations where Trump vowed to "totally destroy" the nation if it threatened the United States or its allies. 

Although the two nations are not formally at war, clearly the two leaders are in a war of words. 

"The United States has great strength and patience, but if it is forced to defend itself or its allies, we will have no choice but to totally destroy North Korea. Rocket Man is on a suicide mission for himself and for his regime," Trump said earlier this week. 

Kim issued a statement Thursday evening, not backing down to Trump's hard-line stance.

"I will make the man holding the prerogative of the supreme command in the US pay dearly for his speech calling for totally destroying the DPRK," Kim said. "Whatever Trump might have expected, he will face results beyond expected." 

"He is unfit to hold the prerogative of supreme command of a country and he is surely a rogue and a gangster fond of playing with fire rather than a politician," Kim added.

Both sides have stepped up their posture toward one another. North Korea has fired missiles over the coast of Japan, and has tested atomic weapons. Meanwhile, the United States has added patrols of the region.