Tensions are escalating so quickly that when an 3.5 magnitude natural disaster was detected in northern North Korea on Saturday in the vicinity of a nuclear test site, it aroused suspicions North Korea had conducted another underground nuclear test.
South Korea's meteorological agency said early indications suggested it was a natural quake because no soundwaves specific to man-made tremors had been identified.
US President Donald Trump called the North Korean leader a "madman" on Friday, a day after Kim dubbed him a "mentally deranged US dotard" who would face the "highest level of hard-line countermeasure in history".
The U.S. Geological Survey reported that a magnitude 3.5 quake occurred at 6:29 p.m. Saturday, Guam time, near Sungjibaegam, North Korea. We can not conclusively confirm at this time the nature (natural or human-made) of the event.
In comments to reporters in New York, North Korea's foreign minister said his country's leader is considering whether to demonstrate his ability to detonate a nuclear warhead aboard a missile sent above the Pacific Ocean.
North Korea's nuclear tests to date have all been underground, and experts say an atmospheric test, which would be the first since one by China in 1980, would be proof of the success of its weapons program. He said Kim was on "suicide mission".
"It is only a forlorn hope to consider any chance that the DPRK would be shaken an inch or change its stance due to the harsher sanctions by the hostile forces", he said, using the abbreviation for North Korea's official name, the Democratic People's Republic of Korea.
Media captionHow would war with North Korea unfold?More news: Chance Warmack seems headed for Philadelphia Eagles' lineup on Sunday
More news: Trump's chance to win out over N Korea with diplomatic solution
More news: Make Your Google Home Smart Speaker Portable With LOFT Battery Base
In another dizzying development Saturday, what seismologists say was a minor natural disaster prompted speculation that Pyongyang could be conducting yet another weapons test.
On Sept. 15, North Korea launched an intermediate-range missile that flew over Japan in its longest-ever flight.
The forceful rhetoric from Pyongyang came after Trump threatened to "totally destroy" North Korea in a speech Tuesday to the General Assembly.
One - titled "We will throw the irrational war fanatics of Trump's gang in the fire of justice" - condemned Trump's United Nations speech as "rubbish". Trump has said he won't allow it, although the U.S.so far has not used military force to impede the North's progress. The Pentagon said the mission in worldwide airspace showed how seriously President Donald Trump takes North Korea's "reckless behavior".
"It is a foolish misjudgment if Trump's gang thinks that America is safe because it's far away from the Korean Peninsula".
Under Kim Jong Un's leadership, Pyongyang carried out several intercontinental ballistic missile tests, including 20 missile tests in 2016.