FILE- In this June 27, 2008 file image from TV, the demolition of the 60-foot-tall cooling tower at its main reactor complex in Yongbyon North Korea. North Korea's Foreign Ministry said Saturday May... (Associated Press) 
 
 SEOUL, South Korea (AP) — North Korea said Saturday that it will dismantle its nuclear test site on May 23-25, in a dramatic event that would set up leader Kim Jong Un's summit with President Donald Trump next month. 
 
 Kim had revealed plans to shut down the country's northeastern testing ground by the end of May during his summit with South Korean President Moon Jae-in last month. Analysts say the closure of the site is mostly symbolic and doesn't represent a material step toward denuclearization. 
 
 In a statement carried by state media, North Korea's Foreign Ministry said that all of the tunnels at the site will be destroyed by explosion, and that observation and research facilities and ground-based guard units will also be removed. 
 
 The North plans to invite journalists from the United States, South Korea, China, Russia and Britain to inspect the process, the statement said. 
 
 Following the Moon-Kim summit, Moon's office said Kim was willing to disclose the process to international experts, but the North's statement Saturday didn't include any mention about allowing experts on the site. 
 
 The North's announcement comes days after Washington announced that the historic summit between Kim and Trump will be held June 12 in Singapore. 
 
 Seoul, which shuttled between Washington and Pyongyang to set up the Trump-Kim meeting, has said Kim has genuine interest in dealing away his nuclear weapons in return for economic benefits. However, there are lingering doubts about whether Kim would ever agree to fully relinquish the weapons he likely views as his only guarantee of survival. 
 
 Kim declared his nuclear forced as complete in December, following the country's most powerful nuclear test to date in September and also three flight tests of intercontinental ballistic missiles designed to reach the U.S. mainland. 
 
 At a ruling party meeting last month, North Korea had already announced that it has suspended all tests of nuclear devices and ICBMs and the plan to close the nuclear testing ground. 
 
 Still, the closure of the site could be a useful precedent for Washington and Seoul as they proceed with the nuclear negotiations with Pyongyang, analysts say. 
 
 "Now that North Korea has accepted in principle that agreements should be verified, U.S. negotiators should hold them to this standard for any subsequent agreement," said Adam Mount, a senior defense analyst at the Federation of American Scientists. "It will make it more difficult for Kim Jong Un to deny inspections now that he has placed them on the table." 
 
 North Korea has invited the outside world to witness the dismantling of its nuclear facilities before. 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 U.S. and four other nations to disable its nuclear facilities in return for an aid package worth about $400 million. ||||| Thank you for your interest in spreading the word about Science. 
 
 NOTE: We only request your email address so that the person you are recommending the page to knows that you wanted them to see it, and that it is not junk mail. We do not capture any email address. ||||| BEIJING—The damage to the nuclear test site that North Korean leader Kim Jong Un has promised to shut down is more extensive than earlier assessments showed, according to a new study by a team of international scientists. 
 
 Space-based radar showed that after the initial impact of North Korea’s latest nuclear test in September last year, a much larger part of the Punggye-ri test site caved in over the following hours and days, according to a study published in Science magazine on Thursday. The study was conducted by researchers from Singapore, Germany, China and the U.S. 
 
 “This means that a very large domain has collapsed around the test site, not merely a tunnel or two,” said Sylvain Barbot, one of the authors who is an assistant professor at Nanyang Technological University in Singapore. 
 
 RUSSIA CHINA Shenyang Punggye-ri nuclear test site NORTH KOREA Pyongyang Sea of Japan (East Sea) Seoul SOUTH KOREA Busan 100 miles JAPAN 100 km 
 
 The research feeds into an international debate over the value of Mr. Kim’s commitment to close the test site in the run-up to last month’s inter-Korean summit and his meeting with President Donald Trump, expected this month or early next. 
 
 Some U.S. officials and experts see the closure as a significant concession while others argue that the site is unusable and its dismantling is therefore an empty gesture designed to gain leverage in negotiations with Seoul and Washington. 
 
 Chinese seismologists involved in a study published last month concluded that a large part of the site was unusable due to the collapse of a cavity inside a mountain there, Mount Mantap, a few minutes after the last test. 
 
 U.S. researchers studying satellite imagery have since argued that, while tunnels may be severely damaged under Mount Mantap—where five of North Korea’s six nuclear tests took place—other parts of the Punggye-ri site are still usable. 
 
 Related Video President Donald Trump and North Korean leader Kim Jong Un both say they want denuclearization, but they may have different definitions of the word. WSJ's Shelby Holliday explains. 
 
 Mr. Kim told South Korean President Moon Jae-in at their summit that two bigger tunnels at the site were still in good condition, according to Seoul’s presidential Blue House. 
 
 The last test caused an initial magnitude-6.3 earthquake, followed by a smaller tremor 8½ minutes later that was triggered by the collapse of damaged rock above the blast cavity, the Chinese study said. 
 
 The new study, which created three-dimensional images of the site, backs the Chinese researchers’ conclusion that a large part of the site can’t be used—while showing that the initial damage is “dwarfed” by the gradual collapse detected from space over the next few hours and days. That damage covers an area with a radius of 800 meters and a height of 400 meters, according to Mr. Barbot, who is also an adjunct professor at the University of Southern California. 
 
 “These findings make us infer that a large part of the Punggye-ri test site is inoperable and that further test may require a substantial investment in the construction of another facility elsewhere,” he said. 
 
 Write to Jeremy Page at jeremy.page@wsj.com
– The nuclear test site that Kim Jong Un promises to shutter may be in worse shape than the world knew, the Wall Street Journal reports. The Punggye-ri site—which is couched in a mountain called Mount Mantap—apparently suffered a sizeable collapse in the hours and days after North Korea's most recent nuclear test in September. An international team of scientists reached this conclusion by combining seismic data with satellite radar images, Nature reports. "These findings make us infer that a large part of the Punggye-ri test site is inoperable," says a USC professor. Seismologists have already shown that a big part of the site was unusable after the last test caused a near-immediate collapse of a cavity in Mount Mantap. The latest study used synthetic aperture radar—which is normally used to make 3D terrain maps—to show that Mantap's slopes moved outward horizontally by nearly four yards, and the summit sank by about half a yard over the next week when "damaged rock above the cavity slowly settled in on itself," says Nature. The latest finding may add to concerns that Kim's plan to close Punggye-ri before meeting President Trump isn't much of a concession. North Korea said Saturday that it plans to dismantle Punggye-ri on May 23-25, the AP reports.