Donald Trump has used his first address to the UN General Assembly to make clear that the US may have no choice but to “totally destroy” North Korea.

With North Korean diplomats sitting just yards from him, Mr Trump said he will have no option to resort to such actions if Pyongyang does not halt the development of its nuclear weapons programme.

In perhaps the most striking piece of sabre-rattling yet, Mr Trump said that unless the regime of leader Kim Jong-un backed down, “we will have no choice than to totally destroy North Korea”.

According to a seating chart of the General Assembly Hall of the New York Headquarters, North Korea was seated in plain view of Mr Trump, in the front row.

However, the senior diplomat for the isolated nation left the room just ahead of Mr Trump’s speech.

In a reference to Mr Kim and a tweet he had sent at the weekend, the US President claimed the North Korean leader appeared to determined to choose a path of self-destruction.

“Rocket man is on a suicide mission for himself and his regime,” he said.

Chatter briefly filled the hall as Mr Trump referred to another by a nickname, on the record of the world body.

Donald Trump urges reform in United Nations debut

He said North Korea’s pursuit of nuclear weapons and ballistic missiles “threatens the entire world with unthinkable cost of human life.”

In what may have been a veiled prod at China, the North’s major trading partner, Mr Trump 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.”

In a speech that appeared to be aimed as much at middle America as at the world leaders listening to him, Mr Trump spent much of his focus on the issue of North Korea’s nuclear weapons programme – something his predecessor, Barack Obama, warned would be likely to be his toughest foreign policy challenge.

He said Pyongyang’s increased testing of intercontinental missiles and nuclear payloads, “threatens the entire world with unthinkable loss of life”.

“If the righteous many don’t confront the wicked few, then evil will triumph,” he said as he called the Kim regime “depraved” and detailed several egregious human rights violations including the death of 22-year-old American college student Otto Warmbier.

Shortly before Trump’s speech, UN Secretary General Antonio Guterres appealed from the General Assembly lectern for statesmanship to avoid war with North Korea.

“We must not sleepwalk our way into war,” said Guterres, the former prime minister of Portugal.

In pictures: North Korea military drill Show all 8 1 /8 In pictures: North Korea military drill In pictures: North Korea military drill North Korea's leader Kim Jong Un watches a military drill marking the 85th anniversary of the establishment of the Korean People's Army (KPA) KCNA/Handout via REUTERS In pictures: North Korea military drill A military drill marking the 85th anniversary of the establishment of the Korean People's Army (KPA) is seen in this handout photo by North Korea's Korean Central News Agency (KCNA) KCNA/Handout via REUTERS In pictures: North Korea military drill A military drill marking the 85th anniversary of the establishment of the Korean People's Army (KPA) is seen in this handout photo by North Korea's Korean Central News Agency (KCNA) KCNA/Handout via REUTERS In pictures: North Korea military drill A military drill marking the 85th anniversary of the establishment of the Korean People's Army (KPA) KCNA/Handout via REUTERS In pictures: North Korea military drill A military drill marking the 85th anniversary of the establishment of the Korean People's Army (KPA) KCNA/Handout via REUTERS In pictures: North Korea military drill This image made from video of still images broadcast in a news bulletin by North Korea's KRT, shows what was said to be a 'Combined Fire Demonstration' held to celebrate the 85th anniversary of the North Korean army, in Wonsan, North Korea. KRT via AP Video In pictures: North Korea military drill This image made from video of still images broadcast in a news bulletin by North Korea's KRT, shows what was said to be a 'Combined Fire Demonstration' held to celebrate the 85th anniversary of the North Korean army, in Wonsan, North Korea. KRT via AP Video In pictures: North Korea military drill This image made from video of still images broadcast in a news bulletin by North Korea's KRT, shows what was said to be a 'Combined Fire Demonstration' held to celebrate the 85th anniversary of the North Korean army, in Wonsan, North Korea. KRT via AP Video

Mr Trump’s speech had started as a defence of his “America First” policies, but descended into a roll call of what he called “rogue nations”, attacking Iran and Venezuela.

The President called the 2015 nuclear deal negotiated by his predecessor Barack Obama and a number of world powers, an embarrassment and hinted that he may not recertify the agreement when it comes up for a mid-October deadline. “I don’t think you’ve heard the last of it,” he said.

He called Iran an “economically depleted rogue state” that exports violence and a “murderous regime”. Denouncing the “dictatorship” of Venezuela leader Nicolas Maduro, Mr Trump called the collapsing situation in the country “completely unacceptable” and said the United States cannot stand by and watch. He warned the United States was considering what further actions it can take.

The main bulk of the start of the 41-minute speech was aimed at setting out a US foreign policy aimed at downgrading global bureaucracies, basing alliances on shared interests, and steering Washington away from nation-building exercises abroad.

Mr Trump, who entered the White House eight months ago, told the 193-member global body that the United States does not seek to impose its will on other nations and will respect other countries’ sovereignty – before then attacking the perils of socialism in relation to Venezuela and Cuba.

He said America needed to take care of its own citizens: “I will always put America first, just like you as the leaders of your countries will always – and should always – put your countries first.”

“I will defend America’s interests above all else,” he said. “But in fulfilling our obligations to other nations we also realise it’s in everyone’s interest to seek a future where all nations can be sovereign, prosperous and secure.”.

US: North Korea could be met with 'massive military response'

As part of that vision, he has called for reform of the UN. During the election campaign, Mr Trump frequently denounced the UN, saying that it was bad for democracy and wasted public money.

He said it was “just a club for people to get together, talk and have a good time” in a December 2016 tweet.

In his first UN meeting on Monday, Mr Trump had said that “in recent years the United Nations has not reached its full potential because of bureaucracy and mismanagement.”

On Tuesday, he did indeed urge the members to meet their financial obligations as he reiterated his commitment to reform the organisation.

At the same time he emphasised that the US would “forever be a great friend to the world and especially to its allies”.

“All responsible leaders have an obligation to serve their own citizens. Our government’s first duty is to its people….In foreign affairs we are renewing this founding principle of sovereignty,” the President claimed, harkening back several times to former President Woodrow Wilson and the Marshall Plan, which aided the rebuilding of Western Europe in the wake of the Second World War.

The speech – especially the rhetoric on North Korea, was met with distain in some quarters. Mr Trump’s bold rhetoric was “embarrassing,” according to Dr Stephen Saideman, an expert and professor at Canada’s Carleton University.

Mr Saideman told The Independent that despite the President’s previous threats of “fire and fury” and appearing to have a fatalistic attitude toward using military options, nothing has really changed.

Swedish Foreign Minister Margot Wallstrom – who crossed her arms when Mr Trump mentioned he could look to “totally destroy”.

“It was the wrong speech, at the wrong time, to the wrong audience,” Ms Wallstrom later said.

Venezuela also rejected the “threats” from a “racist” President Trump.

But Mr Trumps threats aimed at Iran did bring him one fan in Israeli Prime Minister Benjamin Netanyahu, wgo was due to address the world body later on Tuesday, who said: “In over 30 years in my experience with the UN, I never heard a bolder or more courageous speech.“