On Friday, Kim and South Korean President Moon Jae-in vowed "complete denuclearisation" of the Korean peninsula in the first inter-Korean summit in more than a decade, but the declaration did not include concrete steps to reach that goal.
North Korea's state media had said before the summit that Pyongyang would immediately suspend nuclear and missile tests, scrap its nuclear test site and instead pursue economic growth and peace.
Kim told Moon that he would soon invite the experts and journalists to "open to the international community" the dismantling of the facilities, the Blue House said.
"The United States, though inherently hostile to North Korea, will get to know once our talk begins that I am not the kind of person who will use nuclear weapons against the South or the United States across the Pacific," Moon's press secretary Yoon Young-chan quoted Kim as saying.
Kim said there were two additional, larger tunnels that remain "in a very good condition" at the Punggye-ri test site beyond the existing one, which experts have said had collapsed after repeated explosions, rendering much of the site useless.
Kim's promise shows his willingness to "preemptively and actively" respond to inspection efforts to be made as part of the denuclearisation process, Yoon said.
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