https://en.wikipedia.org/wiki/North..._mass_destruction#Defense_Intelligence_Agency
Defense Intelligence Agency[edit]
On August 8, 2017, the Washington Post reported recent analysis completed the previous month by the U.S. Defense Intelligence Agency which concluded that North Korea had successfully produced a miniaturized nuclear warhead that can fit in missiles and could have up to 60 nuclear warheads in its inventory.[5]
Siegfried S. Hecker[edit]
On August 7, 2017, Siegfried S. Hecker, former director of the Los Alamos National Laboratory who has visited North Korea nuclear facilities many times on behalf of the U.S., estimated that North Korea's stockpile of plutonium and highly enriched uranium was probably sufficient for 20 to 25 nuclear weapons. He assessed that North Korea had developed a miniaturized warhead suitable for medium-range missiles, but would need further tests and development to produce a smaller and more robust warhead suitable for an intercontinental ballistic missile (ICBM) and re-entry into the atmosphere. He considered the warhead as the least developed part of North Korea's plans for an ICBM.[151][152]