A high level of activity has been detected at North Korea’s main nuclear complex using satellite images, a think tank said, after leader Kim Jong-un called on Tuesday for increased production of “military nuclear material”. AFP.

Satellite images taken between March 3 and 17 show that the construction of the light water reactor at Yongbyon is “almost complete”, according to the American 38 North.

According to the same images, construction of the building has begun, while water leaks from the cooling system have been detected, indicating that the reactor is “on the verge of starting up”, the think tank said.

The five-megawatt Yongben reactor also continues to operate, and new construction has begun around the uranium enrichment plant, presumably to increase capacity.

“These developments appear to reflect Kim Jong Un’s recent directive to increase the production of fissile material to bolster his nuclear arsenal,” 38 North analyzed.

State media on Tuesday featured North Korea’s No. 1 leader calling for more “nuclear material” for an “exponential” increase in nuclear weapons production, testing a series of smaller warheads that appear to be tactical nuclear warheads.

Experts say the tactical nuclear weapons are a sign that North Korea is making technological progress and suggest the country is preparing for its seventh nuclear test.

For their part, Seoul and Washington have warned of another North Korean nuclear test as early as 2022.

While the two allies have stepped up joint military exercises, Pyongyang has continued to fire and test missiles, accusing Seoul of being behind a deterioration in regional security.

The official KCNA news agency on Sunday condemned a series of joint drills between Washington and Seoul, warning of the “possibility of a nuclear attack” by North Korea.

North Korea’s military, which has ramped up military exercises in recent weeks, said on Tuesday it had conducted a second test of what it called a “nuclear attack underwater drone”.

While Pyongyang has described its status as a nuclear power in 2022 as “irreversible”, North Korea’s leader ordered his military this month to step up military exercises in preparation for a “real war”.

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