Kim announced a moratorium on nuclear and missile testing in April. Pyongyang announced two weeks ago that it had set off explosions and collapsed underground tunnels at it nuclear weapons testing site.
Joseph Bermudez, an expert on Pyongyang's military technology, published a report this week on the website 38 North saying the Iha-ri test site "represented a critical component" in development of medium range missiles and could have been used for testing larger, intercontinental missiles.
"It is unclear whether the destruction of the stand is an indication that the North is suspending this portion of its missile program or that Pyongyang plans to erect other similar facilities in the future," the report adds.
More: Trump says he's ready for Kim summit, which is 'about attitude'
More: U.S., North Korea hammer out summit agenda — and South Korea might join in
What is clear is the continuing thaw in U.S.-North Korea relations. Trump said Thursday that he might even invite Kim to the U.S. if things go well at the summit.
"I think it would be well-received," Trump said. "I think he would look at it very favorably, so I think that could happen."
The Iha-ri test stand was the only known facility for land-based, canister-launched ballistic missile ejection test, the report says. Canister-based missiles allow for more secure transport of missiles over greater distances, protect systems from environmental conditions and reduce launch preparation times.
"This, in turn, has the potential to reduce maintenance requirements, provide for greater tactical flexibility and improve wartime survivability," the report says.
South Korean leader Moon Jae-in has twice met with Kim in recent weeks. The duo agreed to work on a plan to formally end the Korean War that was halted by a temporary armistice in 1953. Kim has said a formal end to the hostilities, along with a pledge from the U.S. not to attack his nation, would essentially eliminate Pyongyang's need for a nuclear arsenal.
Trump is scheduled to meet with Kim in Singapore on Tuesday. Trump had called off the meeting last week after public discourse between the two nations devolved into a torrent of angry rhetoric that had marked the relationship until recent weeks.
Trump accused Kim of showing "open hostility" toward Washington, adding U.S. nuclear weapons are far superior to North Korea's — and "so massive and powerful that I pray to God they will never have to be used."
Trump said Thursday he's ready for the summit, assuring reporters that it will be "much more than a photo-op." He reiterated his long-held position that North Korea must comply with complete and total denuclearization before he considers easing sanctions on the North's economy.
"They have to denuke," Trump said. "If they don’t denuclearize, that will not be acceptable. We cannot take sanctions off."
But most experts are tamping down expectations ahead of the summit. Suzanne DiMaggio, of the New York-based New America think tank, said a joint statement detailing what denuclearization means and setting it as a frim goal would be a success.
“And I think even that will be a challenge to pin down," she said.