Donald Trump has vowed to "totally destroy" North Korea if it threatens the US.
Trump made the comments in an extraordinary speech to the UN General Assembly this afternoon.
The US President said that, if his country's security is jeopardised, it will have no choice but to annihilate the rogue communist state.
Trump also mocked North Korean leader Kim Jong-un, describing him as a "rocket man" who is on a "suicide mission for himself."
The speech marks the latest escalation in tensions between Washington and Pyongyang over recent months.
North Korea has conducted several missile tests and threatened to strike the island of Guam, a US territory in the Pacific Ocean.
In return Trump has talked at length about punishing Kim Jong-un's regime and suggesting the days of diplomacy may be over.