New satellite images indicate North Korea has restarted a reactor at a site used to produce plutonium for its nuclear weapons programme, a think tank has said.

US-based 38 North, which monitors the secretive communist state, said images taken on 22 January suggested operations at the Yongbyon Nuclear Scientific Research Centre had resumed and could be running at a "considerable" level.

Image: The facility is used to produce plutonium. Pic: Pleiades CNES 2017 Distribution Airbus DS

In a report, it said the pictures show "a water plume (most probably warm) originating from the cooling water outlet of the reactor, an indication that the reactor is very likely operating."

Last week, 38 North said satellite images taken on 18 January showed signs that Pyongyang was preparing to restart the reactor with the unloading of spent fuel rods.

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It added the implications of activity at the site "remain unclear except to reaffirm that the Yongbyon facility remains the centre of North Korea's nuclear programme".


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The think tank's latest report comes days after China banned the export of plutonium to North Korea.

In a statement, the Chinese commerce ministry said other prohibited exports included technologies which could aid Pyongyang's programmes to develop nuclear, chemical and biological weapons, as well as the missiles to deliver them.

Just hours after his inauguration, Donald Trump announced plans to develop a "state-of-the-art" missile defence system to protect the US against attacks from Iran and North Korea.

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The President did not provide details on whether the system would differ from those already under development, its cost or how it would be paid for.

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The policy announcement followed reports Pyongyang was preparing to test an upgraded intercontinental ballistic missile prototype.

According to South Korean news agency Yonhap, news of the test appeared to have been intentionally leaked by North Korea to send a "strategic message" to Mr Trump.