South Korean President Moon Jae-in presides over the national security council at the Presidential Blue House in Seoul, South Korea, November 29, 2017.
US President Donald Trump has responded to each test with his own amplified declarations, threatening to "totally destroy" Pyongyang and taunting Kim, saying the North Korean leader was on "a suicide mission".
Kim also stressed North Korea's economic achievements during the speech, and noted the importance of improving the nation's standard of living.
"I regret the government had even lost the flexibility to spend one day or two taking a deep breath and meticulously analysing Kim Jong Un's ulterior motive before hastily issuing a welcoming statement", he said.
South Korea on Tuesday (2 January) offered high-level talks with rival North Korea to find ways to cooperate on next month's Winter Olympics in the South. Seoul's quick proposal after a rare rapprochement overture from Pyongyang a day earlier offers the possibility of better ties after a year that saw a nuclear standoff increase fear of war on the Korean Peninsula.
South Korea has seized and inspected a Panama-flagged ship suspected of selling oil to North Korea at sea in violation of United Nations sanctions, maritime authorities said, according to Yonhap News Agency reported.
In early December, the U.S. began another round of military exercises with South Korea, flying in F-22 fighter jets and other military aircraft.
An official from South Korea's Foreign Ministry said the 5,100-ton KOTI and its crew members were being held at Pyeongtaek-Dangjin port on the country's west coast amid an inspection over supposed "North Korea-related" activity.
In recent months, North Korea conducted its most powerful nuclear test to date and flight-tested intercontinental ballistic missiles three times, raising concerns that it's closer than ever to gaining a military arsenal that can viably target the mainland United States.
But Mullen also said that Trump has disrupted long-held views of the US role in the world, and that America's enemies benefit from that uncertainty.
Turning to relations with South Korea, Kim said, "I sincerely hope the Pyeongchang Winter Olympics will be staged successfully".