Nam also said the increased exchanges between North and South Korea harmed Trump's "maximum pressure" campaign created to force Pyongyang to give up its nuclear weapons.
"The North agreed to permanently close the Tongchang-ri missile engine test site and missile launch facility in the presence of experts from relevant nations", Moon told reporters.
Despite positive steps on Wednesday, both sides have a long way to go ahead of Trump's goal for the complete, verifiable, irreversible denuclearization of the Korean Peninsula, according to Melissa Hanham, a senior research associate at the James Martin Center for Nonproliferation Studies in Monterey, California.
About the recent meeting between Moon and Kim, the former's spokesman Yoon Young-chan said, "It's hard to say at this moment that the two leaders have reached any agreement".
"If and when" they reach an agreement, they would announce it jointly but not take questions, he said.
Moon on Wednesday acknowledged, "there will be challenges and trials, but the more we overcome them the stronger we will become".
"We're starting to get some meat on the bones now", said Daniel Tudor, co-author of "North Korean Confidential". On Wednesday, the Korean leaders signed a joint statement supporting a nuclear weapon-free peninsula to "eliminate all the danger of war", the Associated Press reports.
② The two sides agreed to engage in constant communication and close consultations to review the implementation of the Agreement and prevent accidental military clashes by promptly activating the Inter-Korean Joint Military Committee.
While the two Koreas agreed to establish the buffer zone near the border, known as the Northern Limit Line, Seoul's Defense Ministry said the disputed maritime border was not brought up during the negotiations amid the concern that South Korea might yield concession on its territory.
Though not directly linked to security, the leaders' announcement that they would seek a joint Summer Olympics was a significant move in terms of easing tensions and building trust.
It was announced both governments would cooperate to resolve lingering issues related to separated families from the Korean War.
The United States has criticized North Korea for not doing enough to fulfill the agreement made at the June 12 summit in Singapore. Trump cancelled Secretary of State Mike Pompeo's trip on Pyongyang last month over the impasse. Whatever happens down the road between Kim and Trump, or Kim and whoever follows Trump, since North Korean leaders tend to outlast American presidents, this is to be regarded as a moment of triumph.
Performers hold up cards to form patterns during the "Glorious Country" mass games held in conjunction with the 70th anniversary of North Korea's founding day in Pyongyang on September 9. "Compared with developed countries, (our guesthouse) is a bit shabby", Kim said during a brief chat with Moon.
Moon is expected to speak with Trump after this week's event, and Trump will then decide if he'll accept Kim's invitation. This could be a reference to Kim's insistence that Trump promised he would declare the Korean War to be officially over.
The joint North-South Korean bid marks the latest example of sporting diplomacy between the two countries and comes after athletes from the nations participated on joint teams in three sports - dragon boat racing, lightweight rowing and women's basketball - at the Asian Games.
These talks were meant to be a precursor to a second summit for Kim and Trump.
"South and North Korea have agreed to collaborate closely with the USA and the global community for the final achievement of denuclearization".