North Korea’s Kim Jong Un Poses Next to ‘Miniaturized Nuclear Warhead’

North Korea's Nuclear Program 1:33

North Korean leader Kim Jong Un has been pictured next to what state-run media claimed was a miniaturized nuclear warhead capable of being used on a long-range missile.

The photograph of Kim standing next to the silver spherical object ran in Rodong Sinmun, a newspaper of the ruling Workers’ Party. It came after Pyongyang warned Monday of preemptive nuclear strikes targeting the U.S. and South Korea as a result of the the biggest-ever war games involving both countries.

Kim was quoted as saying the nuclear warheads have been “standardized to be fit for ballistic missiles by miniaturizing them.”

He described the warheads as “thermonuclear” devices, echoing claims that North Korea successfully tested its first “hydrogen bomb” in January.

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"This can be called a true nuclear deterrent," he was quoted as saying.

In South Korea, where the photograph ran on newscasts, officials downplayed Pyongyang's latest claims.

Speaking on condition of anonymity, a South Korean military official told NBC News: "We don't think North Korea has succeeded in miniaturizing nuclear warhead."

Defense ministry spokesman Moon Sang-Gyun gave Reuters a similar assessment of its neighbor's capabilities.

FROM MARCH 7: North Korea Threatens All-Out Response to U.S.-South Korean Military Drills 0:31