Pyongyang has 'successfully produced a miniature nuclear missile warhead'
North Korea has successfully produced a miniaturised nuclear warhead that can fit inside its missiles, crossing a key threshold on the path to becoming a fully-fledged nuclear power, US intelligence officials have concluded.
A confidential analysis, completed last month by the US Defence Intelligence Agency (DIA), comes on the heels of another intelligence assessment that sharply raises the official estimate for the total number of bombs in the communist country's atomic arsenal.
The United States calculated last month that up to 60 nuclear weapons are now controlled by North Korean leader Kim Jong-un. Some independent experts think the number is much smaller.
The findings are likely to deepen concerns about an evolving North Korean military threat that appears to be advancing far more rapidly than many experts had predicted.
US officials concluded last month that Pyongyang is also outpacing expectations in its effort to build an intercontinental ballistic missile (ICBM) capable of striking the American mainland.
US President Donald Trump, speaking at an event at his golf course in Bedminster, New Jersey, said North Korea will face a devastating response if its threats continue.
"They will be met with fire and fury and, frankly, power, the likes of which this world has never seen before," he said.
Earlier, North Korea described a new round of UN sanctions as an attempt "to strangle a nation" and warned that, in response, "physical action will be taken mercilessly with the mobilisation of all its national strength."
Although more than a decade has passed since North Korea's first nuclear detonation, many analysts thought it would be years before the country's weapons scientists could design a compact warhead that could be delivered by missile to distant targets. But the new assessment, a summary document dated July 28, concludes that this critical milestone has been reached.
"The IC (intelligence community) assesses North Korea has produced nuclear weapons for ballistic missile delivery, to include delivery by ICBM-class missiles," the assessment states, in an excerpt read to the 'Washington Post'. Two US officials familiar with the assessment verified its broad conclusions.
It is not known whether the reclusive regime has successfully tested the smaller design, although North Korea officially claimed last year that it had done so.
The US's DIA and Office of the Director of National Intelligence declined to comment.
An assessment this week by the Japanese Ministry of Defence also concludes that there is evidence to suggest that North Korea has achieved miniaturisation.
Mr Kim is becoming increasingly confident in the reliability of his nuclear arsenal, analysts have concluded, explaining perhaps the dictator's willingness to engage in defiant behaviour, including missile tests that have drawn criticism even from closest ally China. On Saturday, China and Russia joined other members of the UN Security Council in approving punishing new economic sanctions, including a ban on exports that supply up to a third of North Korea's annual $3bn (€2.5bn) in earnings.
The nuclear progress further raises the stakes for Mr Trump, who has vowed North Korea will never be allowed to threaten the United States with nuclear weapons. In an interview broadcast on Saturday on MSNBC's 'Hugh Hewitt Show', national security adviser HR McMaster said the prospect of a North Korea armed with nuclear-tipped ICBMs would be "intolerable, from the president's perspective".
"We have to provide all options . . . and that includes a military option," he said. But Mr McMaster said the administration would do everything short of war to "pressure Kim Jong-un and those around him, such that they conclude it is in their interest, to denuclearise."
The options said to be under discussion range from new multilateral negotiations to reintroducing US battlefield nuclear weapons to the Korean Peninsula, officials familiar with internal discussions said.
At the same time, the administration has been attempting to push North Korea toward talks, but Pyongyang has shown no interest in dialogue.
Determining the precise make-up of North Korea's nuclear arsenal has long been a challenge for intelligence officials because of the regime's culture of extreme secrecy and insularity. The country's weapons scientists have conducted five nuclear tests since 2006, the latest being a 20 to 30-kiloton detonation on September 9, 2016, that produced a blast estimated to be up to twice that of the bomb dropped on Hiroshima, Japan, in 1945.
But producing a compact nuclear warhead that can fit inside a missile is a technically demanding feat, one that many analysts thought was still beyond North Korea's grasp.