Speaking to reporters on Monday, a South Korean military official said the military is maintaining a strong defense posture in preparation for what the official called the "worst-case scenario" of the North conducting a nuclear test in the near future.
Another military official said that by looking at the missiles that North Korea recently tested, and because Kim Jong-un in April mentioned "tactical nuclear weapons," the regime has been focusing on miniaturizing these weapons for the past several years.
In fact, there has been a lot of speculation that the North will carry out its seventh nuclear test for the purpose of developing smaller and lighter nuclear weapons.
As for the timing, many experts say the North is almost ready for the next test, but it's up to Kim Jong-un to make the final decision.
Earlier in the day, President Yoon Suk-yeol also mentioned in his speech to parliament that North Korea is showing signs of preparing for a nuclear test.
"Two days after I took office on May 12th, North Korea fired three missiles. This was their 16th show of force this year, and the North was also seen preparing for a nuclear test."
Since March, satellite images have shown signs that Pyeongyang is restoring one of the tunnels at the Punggye-ri nuclear test site a tunnel that was demolished a few years ago.
The North has carried out nuclear tests six times since 2006.
If it does manage to conduct another test, it'd be the first one in nearly five years.
Bae Eun-ji, Arirang News.