The display at Punggye-ri, in the northwest of the country will be open to foreign media.
The event marks another step in leader Kim Jong Un’s charm offensive. A ceremony scheduled between May 23-25, weather permitting, said the foreign ministry.
The journalists will be provided with a charter flight from Beijing to the North Korean coastal city of Wonsan, from where they will travel by train to the test site.
The ministry said the North will continue to “promote close contacts and dialogue with the neighboring countries and the international society so as to safeguard peace and stability on the Korean Peninsula and over the globe.”
Dialogue brokered by Seoul has seen US-North Korea relations go from trading personal insults and threats of war last year to a summit between Kim and President Donald Trump due in Singapore on June 12.
But skeptics warn that Pyongyang has yet to make any public commitment to give up its arsenal, which includes missiles capable of reaching the United States.
Washington is seeking the “complete, verifiable and irreversible denuclearization” of the North and stresses that verification will be key.
Punggye-ri has hosted all six of the North’s nuclear tests, the latest and by far the most powerful in September last year, which Pyongyang said was an H-bomb.
Kim has declared the development of the North’s nuclear force complete and that it had no further need for the site.
The latest measures will see the tunnels of the test site blown up and their entrances completely blocked, Pyongyang’s foreign ministry said, according to the official KCNA news agency.
All observation facilities and research institutes would be removed, along with guards, it said, “and the surrounding area of the test ground be completely closed”.
Reporters from China, Russia, the United States, Britain and South Korea would be allowed to cover the event on site to show it “in a transparent manner”.
Limits on foreign journalists were due to space constraints, it said, as the site was in an “uninhabited deep mountain area”.
Analysts said the move was positive but limited in its scope.
It was “not bad, but a cost-free signal”, tweeted MIT political science professor Vipin Narang.
Given the stage it had already reached, Pyongyang “may feel like they don’t need to test anything for a while”, he said.
Jeffrey Lewis, of the Middlebury Institute for International Studies, expected that the North “will sanitize the site before letting anyone see it”.
In June 2008, international broadcasters were allowed to air the demolishing of a cooling tower at the Nyongbyon reactor site, a year after the North reached an agreement with the US and four other nations to disable its nuclear facilities in return for an aid package worth about $400 million.
But in September 2008, the North declared that it would resume reprocessing plutonium, complaining that Washington wasn’t fulfilling its promise to remove the country from the US list of state sponsors of terrorism.
The administration of George W. Bush removed North Korea from the list in October 2008 after the country agreed to continue disabling its nuclear plant. However, a final attempt by Bush to complete an agreement to fully dismantle North Korea’s nuclear weapons program collapsed that December when the North refused to accept US-proposed verification methods.
The North went on to conduct its second nuclear test in May 2009.