U.S. intelligence officials believe that North Korea is constructing new intercontinental ballistic missiles capable of reaching the mainland United States, according to a bombshell report by the Washington Post.

Published Monday, the report claims that U.S. spy agencies have seen evidence that the regime is developing one or two new liquid-fueled intercontinental-range ballistic missiles (ICBM) at a factory outside Pyongyang, similar to the Hwasong 15, which was first tested last November.

Sources speaking to the Diplomat claim that the development of at least one of those new missiles began after the Singapore summit of between North Korean leader Kim Jong Un and President Donald Trump on June 12.

The claims of increased activity at the Sanumdong facility are backed up by commercial satellite imagery from Planet Labs that show that two new buildings have been constructed at the site in recent weeks.

The buildings were not visible on imagery from June 5, just days before Kim traveled to Singapore to meet Trump. One of the new buildings is a museum, suggesting the site is of significant importance to Kim, and is unlikely to be decommissioned any time soon.

Kim does however appear to be following through on his promise to dismantle the Sohae Satellite Launching Station, but analysts believe this is a purely symbolic effort and that the launch pad could be reassembled in secret in a matter of months.

On top of the increased activity at the missile site in Sanumdong, recent reports suggest that North Korea is continuing to produce nuclear material at a secret enrichment site in Kangson.

Last week U.S. Secretary of State Mike Pompeo tacitly acknowledged this during Senate testimony when he said Pyongyang’s facilities “continue to produce fissile material” for nuclear weapons.

The latest reports are seen as further evidence that Trump’s claim following his summit — that Pyongyang was “no longer a nuclear threat” — is simply not true.

Trump has yet to react to the news, but John Hemmings, Asia Director at the Henry Jackson Society, a British foreign policy think tank, says there are three ways the White House could view the latest developments:

“If you’re an opportunist, it’s because the [North Korean] regime wants as much leverage as possible in the coming negotiations with Trump as they move from denuclearisation to enriching the North Korean economy; if you’re a pessimist, they are simply building up their capacity to strike and thus deter the U.S. from involvement in any future ROK-DPRK conflict. However, if you’re a realist, it’s because Kim Jong Un genuinely wants economic growth, but he wants to see if he can keep his weapons at the same time: a classic cake-and-eat-it situation,” Hemmings told VICE News.

Intelligence sources speaking to the Washington Post believe that North Korea’s strategy is to deceive Washington in relation to the number of nuclear warheads and missiles they have. The strategy includes saying they have disposed of 20 warheads and claiming they have fully denuclearized, while retaining dozens more in secret.

For most North Korea watchers there is little shock that Pyongyang has not stopped its missile and nuclear programs given how hard they fought to develop them, and how crucial they are when it comes to any future talks with the U.S.

“It is not a surprise that North Korea may continue to develop its missile capabilities to make its threat to the U.S. more credible,” Baohui Zhang, director of the Centre for Asian Pacific Studies at Lingnan University in Hong Kong, told VICE News. “That credibility in turn strengthens North Korea’s bargaining power in negotiations.”