World powers expressed outrage Friday after North Korea claimed it had successfully tested a nuclear warhead that could be mounted on a missile, prompting urgent UN talks and calls for new sanctions. South Korea, the United States, Japan, Russia and China all condemned the blast at the Punggye-ri nuclear site, which was the North's fifth and most powerful yet at 10 kilotons. "The patience on our side and that of the international community has already reached its limit," South Korean President Park Geun-Hye said, slamming the North's young leader, Kim Jong-Un, for his "maniacal recklessness".
The news drew swift condemnation from US President Barack Obama who called the test "a grave threat to regional security and to international peace and stability" and vowed to push for new international sanctions.
Japan condemned the test as "absolutely unacceptable", Russia expressed "extreme concern", and the head of the UN atomic watchdog said it was a "clear violation" of numerous Security Council resolutions.
At the request of the United States and Japan the Security Council announced it would meet at 1900 GMT Friday for urgent talks on North Korea.
Obama said he had called the leaders of South Korea and Japan to confer over the crisis, with Park and Japanese leader Shinzo Abe also agreeing to cooperate closely with each other.
Pyongyang's state media said the test, which comes after a series of ballistic missile launches, had realised the country's goal of being able to fit a miniaturised warhead on a rocket.
"Our nuclear scientists staged a nuclear explosion test on a newly developed nuclear warhead at the country's northern nuclear test site," a North Korean TV presenter said.
First indications of an underground explosion came when seismic monitors detected a 5.3-magnitude “artificial earthquake” near the Punggye-ri nuclear site.
“The 10-kiloton blast was nearly twice the (power of the) fourth nuclear test and slightly less than the Hiroshima bombing, which was measured about 15 kilotons,” said Kim Nam-Wook from the South’s meteorological agency.
But attention soon shifted from the power of the blast to Pyongyang’s claim that it was a miniaturised warhead. If Pyongyang can make a nuclear device small enough to fit on a rocket — and bolster the range and accuracy of its missiles — it might achieve its oft-stated aim of hitting US targets. But its past claims to have achieved this have been discounted.
However, North Koreans who gathered around public screens to watch the official announcement of the test — which came on the 68th anniversary of the country’s founding — were approving. “US bastards may be saying this and that, but we fear nothing as our military power has strengthened further,” said one woman, who did not give her name. Ordinary North Koreans usually express only officially-sanctioned views when questioned by foreign news organisations. Pyongyang routinely insists Washington is on the verge of launching all-out war against it.
The test came as American and South Korean forces staged a re-enactment of the Incheon landing, 66 years after the start of Operation Chromite, the battle that turned the tide in the Korean War. Outside experts said authenticating North Korea’s claim to have mastered miniaturisation would be difficult using seismic data alone. “We would need to see it tested on a missile, like China did in the 1960s,” said Melissa Hanham, a North Korea expert at the Middlebury Institute of International Studies.