DONALD Trump has made his strongest threat yet against North Korea, vowing to "totally destroy" the country if it attacks the US or its allies.

In a wideranging speech to the United Nations General Assembly in New York overnight, the US President repeated his mocking nickname for Kim Jong-un - "Rocket Man" - and slammed his leadership as a "depraved regime".

"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," he said.

"Rocket Man is on a suicide mission for himself and for his regime.

"The United States is ready, willing and able, but hopefully this will not be necessary."

In a dark and forceful 40-minute address that identified rogue regimes as the "scourge of our planet today", Mr Trump reserved his strongest condemnation for the hermit kingdom.

"No one has shown more contempt for other nations and for the wellbeing of their own people than the depraved regime in North Korea," he said, without ever referring to Mr Kim by name.

"It is responsible for the starvation deaths of millions of North Koreans and for the imprisonment, torture, killing and oppression of countless more."

The President pointed to the death of American university student Otto Warmbier, the assassination of Mr Kim's brother and the enslavement of a 13-year-old Japanese girl as proof of the regime's wickedness.

American student Otto Warmbier speaks as he is presented to reporters in Pyongyang, North Korea. More than 15 months after he gave a staged confession in North Korea, he was brought home to the US and died shortly after
American student Otto Warmbier speaks as he is presented to reporters in Pyongyang, North Korea. More than 15 months after he gave a staged confession in North Korea, he was brought home to the US and died shortly after AP Photo/Kim Kwang Hyon

"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."

He added: "It is time for North Korea to realise that the denuclearisation is its only acceptable future."

Mr Trump thanked China and Russia for signing on to two sets of UN Security Council sanctions against North Korea, but said "we must do much more".

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

Mr Trump implored the UN members to "confront together those who threaten us with chaos, turmoil and terror" - such as North Korea, Iran and Syria.

"They respect neither their own citizens nor the sovereign rights of their countries," he said.

"If the righteous many do not confront the wicked few then evil will triumph.

"When decent people and nations become bystanders to history, the forces of destruction only gather power and strength."


Before Mr Trump's Tuesday speech, the White House promised that it would be a "deeply philosophical" address. The philosophy that Mr Trump encouraged UN members to embrace was that patriotism, democracy and the people each nation serves should be central to leaders' decision-making.

"We are calling for a great reawakening of nations, for the revival of their spirits, their pride, their people and their patriotism," he said towards the end of his speech.

"History is asking us whether we are up to the task. Our answer will be a renewal of will, a rediscovery of resolve and a rebirth of devotion.

"We need to defeat the enemies of humanity and unlock the potential of life itself."

The Trump we saw on Tuesday was much more disciplined and rhetorical than the one we usually see. He stuck to the script of his speech, which was heavy on big ideas and light on Trumpisms. (Although, he did sneak in references to Mr Kim as "Rocket Man" and to "loser terrorists".)

Touching upon a booming US stock market, a recovering Europe, a diminished middle class and the threat of terrorism, his speech bounced between the two poles of hope and horror.

"We meet at a time of both immense promise and great peril," he said.

"It is entirely up to us whether we lift the world up to new heights or let it fall into a valley of disrepair."

He encouraged other nations to follow his "America first" doctrine and put their own interests first.

"We do not expect diverse countries to share the same cultures, traditions or even systems of government, but we do expect all nations to uphold these two core sovereign duties: to respect the interests of their own people and the rights of every other sovereign nation," he said.


Mr Trump also took direct aim at the "reckless regime" and "corrupt dictatorship" of Iran, which he said "speaks openly of mass murder, vowing death to America, destruction to Israel and ruin for many leaders and nations in this room".

The 72nd United Nations General Assembly at at UN headquarters in New York. EPA/PETER FOLEY
The 72nd United Nations General Assembly at at UN headquarters in New York. EPA/PETER FOLEY

The President's speech was interrupted with applause when he criticised the Iran nuclear deal, which the US signed under former president Barack Obama.

"We cannot let a murderous regime continue these destabilising activities while building dangerous missiles and we cannot abide by an agreement if it provides cover for the eventual construction of a nuclear program," he said.

"The Iran deal was one of the worst and most one-sided transactions the United States has ever entered into.

"Frankly, that deal is an embarrassment to the United States and I don't think you've heard the last of it - believe me."


Mr Trump said "major portions" of the world were "going to hell" as part of his push for the UN to focus less on bureaucracy and more on results.

He outlined his views on UN reform in a speech on Monday, where he said the organisation had "not reached its full potential because of bureaucracy and mismanagement".

"While the United Nations on a regular budget has increased by 140 per cent, and its staff has more than doubled since 2000, we are not seeing the results in line with this investment," he said.

He elaborated on this comments on Tuesday: "Major portions of the world are in conflict and some in fact are going to hell but the powerful people in this room, under the guidance and auspices of the United Nations, can solve many of these vicious and complex problems."

Mr Trump also complained that the US had funded a greater share of the UN than was fair and called on other nations to shoulder more of the burden.