North Korea on Saturday issued another threat against the United States and said that targeting America with its rockets was inevitable after "Mr Evil President" Donald Trump called their leader "rocket man" on an international stage.

Trump, in his first address to the United Nations General Assembly (UNGA), had vowed to annihilate North Korea if Washington or its allies are threatened. In a warning to Pyongyang, 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."

Calling North Korean leader Kim Jong-Un a 'Rocket man', the US President had said: ''Rocket Man is on a suicide mission for himself."

Donald Trump
US President TrumpReuters

North Korean Foreign Minister Ri Yong Ho's remarks came hours after US Air Force B-1B Lancer bombers escorted by fighters flew in international airspace over waters east of North Korea in a show of force.

The US bombers' flight was the farthest north of the demilitarised zone separating North and South Korea that any US fighter jet or bomber has flown in the 21st century, the Pentagon said, according to Reuters.

"This mission is a demonstration of US resolve and a clear message that the president has many military options to defeat any threat," said Pentagon spokeswoman Dana White.

The week has been riddled with the US President and the North Korean leader Kim Jong-Un trading insults, with Trump calling Kim a "madman", a day after Kim branded him as a "mentally deranged US dotard."

Kim Jong Un
North Korean leader Kim Jong-UnReuters

The mudslinging between the nations continued on Saturday when Ri called Trump a "deranged person full of megalomania and complacency" who is trying to turn the United Nations into a "gangsters' nest". The foreign minister added that Trump himself was on a "suicide mission."

"Now, we are finally only a few steps away from the final gate of completion of the state nuclear force," Ri said in his address at the UNGA.

The North Korean minister said that the sanctions imposed on his nation by the UN will have no effect on  Pyongyang's resolve to develop its nuclear weapons, with the ultimate goal being "balance of power with the US."

Trump, on Thursday, had announced fresh US sanctions which allow targeting of companies and institutions that finance and facilitate trade with North Korea.

After North's latest missile launch and the sixth nuclear test, the US had suggested that its patience for diplomacy with Pyongyang was running out. With North Korea's growing nuclear programme, unbridled missile tests, and the US' threats of military action, a highly plausible prospect of a nuclear war looms over the world.