U.S. Secretary of State Mike Pompeo said the Trump administration is not willing to invest taxpayer dollars into North Korea relations, but they are open to "lift sanctions" and allow private American investment in the totalitarian state.
North Korea has begun dismantling the country's only known nuclear test site, according to satellite photos, following through on a promise made by leader Kim Jong-un ahead of his meeting with Donald Trump.
But President Donald Trump, South Korean President Moon Jae-in and others have welcomed the decision, saying it's a measure of the North's sincerity in its recent outreach to the worldwide community.
The move comes ahead of leader Kim Jong Un's summit with Mr Trump next month.
USA ambassador Robert Wood meanwhile told the same forum that his country "welcomes the professed commitment by North Korea to end nuclear tests and missile launches and the shut-down of its nuclear test site".
The two largest buildings at the command center and the main administrative support area remained intact, and no tunnel entrances appear to have been permanently closed, 38 North said.
If Kim makes such a change, he said, "President Trump is prepared to assure that there's going to be a successful transition".
"We hope the sound of the dynamite blowing up the tunnels at Punggye-ri will be the first salute in our journey towards a nuclear-free Korean peninsula", the South's presidential spokesman said.
Still, the closure of the underground testing site could be a useful precedent for Washington and Seoul as they proceed with the nuclear negotiations with Pyongyang, analysts say. "They are in great need of agricultural equipment and technology", he said on CBS' "Face the Nation".
Jeffrey Lewis, director of the East Asia Nonproliferation Program at California's Middlebury Institute of International Studies, said in a blog post this week that recent satellite images had shown the removal of some buildings from the site.
The North Korean announcement said the ceremony would take place between May 23 and 25, weather permitting.
American nuclear weapons expert Siegfried Hecker, a professor emeritus at Stanford University, led a group of USA scientists to North Korea's Yongbyon nuclear complex in November 2010.
South Korea had no immediate response to the statement. "That we won't do the traditional model where they do something, and we give them a bunch of money, and then both sides walk away". Pompeo said that the US was willing to help the impoverished North boost its economy to levels like those in prosperous South Korea.
South Korea's deputy nuclear envoy Jeong Yeon-doo will visit the International Atomic Energy Agency (IAEA) in Vienna this week to discuss the "complete denuclearisation of North Korea" the foreign ministry said on Sunday. The United States is another, though Washington has signed the treaty, which Pyongyang has not. "If North Korea shuns them, it will once again face criticism that the dismantlement was just for show".