North Korea can create more materials for nuclear bombs than originally thought, the United States says.
The country’s nuclear capacity is of a different level to previously thought, according to a report by the US Nuclear Threat Initiative (NTI).
NTI said in its latest quarterly report that North Korea has a “significant nuclear inventory”, but does not yet have an operational nuclear weapon.
The Pentagon declined to comment on the contents of the report, which was dated earlier this month.
North Korea has carried out three nuclear tests since 2006 and has been seeking to upgrade its nuclear arsenal to enable it to mount a nuclear warhead on a ballistic missile.
NTI’s executive director, Daryl Kimball, warned that the threats posed by North Korea’s nuclear programme cannot be managed for the next 10 to 15 years “on a reactive basis”.
“We must get ahead of it before North Korea can do something truly catastrophic to the international order,” he said.
NTI says North Korea can now produce fuel for nuclear weapons by rolling out enriched uranium or plutonium to reactors, and can make a more efficient version of a plutonium fuel cycle.
This can be achieved using centrifuges, rather than more traditional uranium enrichment facilities, which increases the level of radiation exposure to the uranium fuel, it says.
“Rapid expansion of North Korea’s nuclear programme and development of new programmes would make Pyongyang dependent on other countries for critical components – uranium, plutonium or both,” it said.
North Korea’s nuclear programme “threatens American interests globally, including in South Korea and Japan”, and places “significant and enduring strain” on the relationship between the US and North Korea, it adds.
But Mr Kimball rejected claims by North Korea that Washington was treating Pyongyang as an enemy and insisting on regime change.