President Donald Trump said the U.S. will "totally destroy North Korea" if forced to defend itself during a speech before the United Nations on Tuesday.

Trump, who recently referred to North Korean dictator Kim Jong Un as "Rocket Man" in a tweet, used the term again during his first speech before the U.N. General Assembly. Castigating North Korea's nuclear ambitions and belligerent behavior, he called on the body to unite against the rogue regime.

I spoke with President Moon of South Korea last night. Asked him how Rocket Man is doing. Long gas lines forming in North Korea. Too bad! — Donald J. Trump (@realDonaldTrump) September 17, 2017

"No nation on earth has an interest in seeing this band of criminals arm itself with nuclear weapons and missiles," Trump said. "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."

Hopefully, Trump said, such an action will not be necessary, calling on the U.N. to perform its stabilizing role. Trump thanked Russia and China for joining in recent unanimous Security Council votes to impose sanctions against the rogue country, but he said more has to be done.

"It is time for all nations to work together to isolate the Kim regime until it ceases its hostile behavior," he said.

"When decent people and nations become bystanders to history, the forces of destruction only gather power and strength," he said. "No one has shown more contempt for other nations and for the well-being of their own people than the depraved regime in North Korea."

Trump recalled the regime's recent "deadly abuse" with the story of Otto Warmbier, the American college student who was detained in North Korea for a year-and-a-half and returned to the U.S. in a coma. He died a few days a later.

"If this is not twisted enough, now North Korea's reckless pursuit of nuclear weapons and ballistic missiles threatens the entire world with unthinkable loss of human life," he said. "It is an outrage that some nations would not only trade with such a regime, but would arm, supply and financially support a country that imperils the world with nuclear conflict."

The Trump administration has called on China, as North Korea's chief trading partner, to do more to press the Kim regime into coming to the negotiating table.