The imagery, captured by Planet Labs and analyzed by experts at the Middlebury Institute of International Studies, indicates that the facility, which is in the village of Wollo-ri near the country's capital city of Pyongyang and has not been previously disclosed to the public, is believed to be linked to North Korea's nuclear program and remains active.
"It has all the signatures of a North Korean nuclear facility -- security perimeter, on-site housing, monuments to unpublicized leadership visits, and an underground facility. And it sits right next to a bottled water factory that has none of those characteristics," Jeffrey Lewis, a professor at the Middlebury Institute of International Studies, which specializes in open-source intelligence, told CNN prior to publishing his own report.
"The big thing that sticks out is all the vehicle traffic -- cars, trucks, shipping containers. This factory is very active. That activity has not slowed down -- not during negotiations and not now. It's still making nuclear weapons," he told CNN.
While the facility was identified in 2015 by researchers at the James Martin Center for Nonproliferation Studies, Lewis and his fellow researchers previously chose not to publicize the facility because they could not identify its specific role within North Korea's nuclear program.
However, the publication of the site's name and function in a forthcoming book written by Ankit Panda, a North Korea expert who works for the Federation of American Scientists, makes its location a matter of public interest, they told CNN.
In his book, titled "Kim Jong Un and the Bomb," Panda writes that the facility is thought to be primarily associated with manufacturing warheads and could also serve as a storage location for those weapons should North Korean leader Kim Jong Un need to disperse his stockpile "for better responsiveness in a crisis," according to passages obtained by CNN.
"We'd been looking at this site for a long time and knew it was associated with the nuclear program. When Ankit Panda asked me if we knew about a site near someplace called Wollo-ri that was involved in making nuclear weapons, it all clicked," Lewis said.
The CIA and Pentagon declined to comment when asked if the facility is believed to play a role in North Korea's nuclear program.
It also comes as talks between Washington and Pyongyang remain stalled.
US officials, including Secretary of State Mike Pompeo, have continued to insist that the Trump administration remains focused on North Korea's complete denuclearization, despite the fact that Kim never formally agreed to such terms and intelligence officials maintain that Pyongyang has little intention of surrendering its weapons stockpile.
A United Nations report produced earlier this year revealed that North Korea continued to develop its weapons program in 2019, violating long-standing UN Security Council sanctions. One section of the report reviewed by CNN said North Korea's ballistic missile program was "characterized by its intensity, diversity and coherence."
Meanwhile, North Korean state media has said in recent months and weeks that the country's leaders have no immediate intention of engaging in the type of high-level talks with the US that took place last year.
"Kim Yo Jung's provocative gestures and Kim Jong Un's follow actions are likely calculated," a South Korean official told CNN this week. South Korea is still trying to coordinate talks between the US and North Korea but it appears Pyongyang has not responded, the official added, using a different spelling for Kim's name.
Additionally, former national security adviser John Bolton has repeatedly said while promoting his new book that Trump has been played by Kim and the threat from North Korea is "absolutely greater" today than it was prior to two summits between the leaders since 2018.
"The idea that just this oleaginous layer of compliments to this brutal dictator would convince him that you could make a deal with Donald Trump, I thought, was both strikingly nave and dangerous," Bolton told ABC News in an interview last month.
"The threat from North Korea today is absolutely greater. Because while all these photo opportunities were taking place, there's absolutely no doubt that North Korea's work on both its nuclear and ballistic missile programs continued. It's one of the most secretive societies on the planet," he said.
State Department Deputy Secretary Steve Biegun will likely try to avoid discussing the claims made by Bolton when he meets with his South Korean counterparts this week, and he plans to have a frank discussion about President Moon Jae-in's new national security leadership, as some of those officials have relationships with North Koreans, a US official and another source familiar with his plans told CNN on Tuesday.
Moon recently named Park Jiewon, a former lawmaker and presidential chief of staff, as the country's new spy chief.
Park is one of South Korea's foremost experts on the North, but, like Moon, has been criticized by conservatives for being too close to Pyongyang. Park was sentenced to prison for secretly sending money to the North in order to arrange the inter-Korean summit in 2000.
While meeting with his South Korean counterpart, Biegun will reinforce the US position that there will be no sanctions relief for North Korea unless there is denuclearization. He is also expected to urge South Korea's Ministry of Foreign Affairs to maintain its working group with the US, though that group has faced some criticism from Moon's new national security team, the sources said.
Biegun said Wednesday that the US is ready to restart talks with North Korea once Kim appoints a "prepared and empowered" lead negotiator but that the administration had not requested a meeting ahead of his visit to Seoul.
"When Chairman Kim appoints a counterpart to me, who is prepared and empowered to negotiate on these issues, they will find us ready at that very moment. Dialogue can lead to action, but action is impossible without dialogue," he said.
Meanwhile, recent satellite imagery suggests North Korea continues to actively build up its nuclear weapons stockpile at sites like Wollo-ri, which "has a number of signatures suggesting that it has a role in the DPRK's nuclear program," experts told CNN.
"The site is distinguished by a strong security perimeter and what appears to be several high-rise residential buildings on site (next to a tree-lined pond)," Lewis and fellow researchers Catherine Dill, David Laboon and David Schmerler said.
"North Korea tends to emphasize the construction of better housing as a perk for scientists and technicians involved in the nuclear and missile programs. Placing that housing on site and within a security perimeter separates the personnel at the facility from the neighboring community," experts added. "Moreover, although there are monuments at the Wollo-ri site that indicate leadership visits, we find no state media reports on any such visits. These are all characteristics of other DPRK nuclear facilities."
Additionally, the site appears to contain an underground facility, according to satellite images, though experts acknowledge it is difficult to assess how extensive that facility is.
"The site itself is set against a hillside substantial enough to accommodate an underground facility (see figure below) and is extensively terraced. A number of buildings could serve as entrances to such a facility," Lewis and his team write.
Satellite photos also reveal consistent vehicle movement at the site, indicating it remains active and has a continuing role in North Korea's nuclear development, according to analysts from the Middlebury Institute.
"Vehicle traffic at the site suggests that manufacturing at Wollo-ri continued during the summit process that stretched from the meeting in Singapore in June 2018 to the June 2019 meeting between Trump and Kim in the DMZ," they said.
"Recent satellite images show that vehicle traffic continues, suggesting that the DPRK continues to manufacture nuclear warheads or their components," the experts added.
CNN's Kylie Atwood and Joshua Berlinger contributed to this report.