They went on: "We are convinced that the Korean people closely united around Supreme Leader Kim Jong-un will win in the struggle to build a powerful socialist nation and reunify the country". North Korea later fired a ballistic missile over Japan and the USA military flew powerful bombers and stealth fighter jets over the Korean Peninsula and near Japan in a show of force against the North. Ri retorted that Trump himself was on a "suicide mission" after the USA president said Kim was on such a mission.
As with much that has transpired lately in the U.S.
On Thursday President Trump announced additional sanctions by the United States that target companies and financial institutions that are large trading partners and suppliers of finance to the North.
It is "a forlorn hope to think that we will be shaken...by hostile forces", Ri said Saturday.
The U.S. Geological Survey said it could not conclusively confirm whether the quake, which it measured at magnitude 3.5, was manmade or natural.
"I will make the man holding the prerogative of the supreme command in the USA pay dearly for his speech calling for totally destroying the DPRK", said the statement carried by North's official Korean Central News Agency on Friday morning.
The U.S. bombers' flight was the farthest north of the demilitarized zone separating North and South Korea that any U.S. fighter jet or bomber has flown in the 21st century, the Pentagon said. It does, however, raise many questions, including: How would the North undertake such a nuclear test, what risks might it pose to Japan and how would the US respond?
"We are prepared to use the full range of military capabilities to defend the USA homeland and our allies".
Mr Kim's words follow the US President's threat to "totally destroy" North Korea, comments described by the North Korean dictator as "the most ferocious declaration of a war in history". In response, the United Nations passed a range of new sanctions against North Korea, including petroleum and textiles restrictions.
China accounts for around 90 per cent of North Korea's trade, so Beijing's cooperation is critical to any efforts to derail Pyongyang's development of nuclear weapons and long-range missiles.
China's quake administration said the tremors in North Korea were felt at 08:30 hours (GMT). He suggests a deal in which the North would agree to halt missile flights over Japan or South Korea and the US would agree to stop its strategic bomber training flights within a certain distance of the North Korean border.
Overnight, seismic activity was detected near the area where North Korea conducted its most recent nuclear test, and China's state news agency said it was because of an explosion.
All six of North Korea's nuclear tests thus far, dating to 2006, have been conducted in underground tunnels.
Tensions have continued to rise around the Korean peninsula since Pyongyang carried out its sixth nuclear test, prompting a new round of United Nations sanctions.
The forceful rhetoric from Pyongyang came after Trump threatened to " totally destroy" North Korea in a speech to the UN General Assembly on Tuesday.
A handful of North Korea analysts believe Kim's response - the first time he has ever released a first-person statement - could show how personally the young leader took Trump's speech.