President Donald Trump has declared that some parts of the world “are going to hell”.

In his first address to the United Nations General Assembly – during which he called Iran a “murderous regime” and threatened to “totally destroy North Korea” – Mr Trump suggested that the UN has the potential to resolve many of the world's most complicated issues.

“Major portions of the world are in conflict and some, in fact, are going to hell,” the President said. “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's use of stark language during his speech was a departure from the softer tone he took during his first day at the UN.

“We pledge to be partners in your work,” Mr Trump told a room full of world leaders on Monday as he embraced an effort to fix the organisation. “And I am confident that if we work together and champion truly bold reforms, the United Nations will emerge as a stronger, more effective, more just and greater force for peace and harmony in the world.”

On Tuesday, the President again reiterated his support for the UN – an organisation which he heartily criticised on the campaign trail – as well as restated that the US bears an unfair share of its costs.

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“The United States bears an unfair cost burden, but – to be fair – if it could actually accomplish all of its stated goals, especially the goal of peace, this investment would easily be well worth it,” Mr Trump said.