Diplomatic fallout | Leading article | North's hello to Obama | Comment: show of weakness

The UN Security Council unanimously condemned North Korea last night for carrying out a powerful underground nuclear test. It appeared paralysed on whether to impose further sanctions on the communist regime.

President Obama said that the test was a threat to world peace.

The atomic bomb — up to 20 times more powerful than the previous one detonated by North Korea in 2006 — was comparable with the one that flattened Hiroshima. It put the world on notice that Pyongyang is accelerating quickly towards a military nuclear capability. Three short-range missiles were also tested, prompting South Korea to put its army on alert.

The provocative test sparked global condemnation, even from China, the reclusive state’s only ally. It was clear, however, that the West was increasingly powerless to halt the nuclear programme.

Susan Rice, Mr Obama’s ambassador to the UN, conceded that it would be premature to predict new sanctions. She said that the US would seek “strong measures”. Only France called for fresh sanctions against Pyongyang.

Mr Obama said that the test was a great threat to the peace and a blatant violation of international law. Gordon Brown called it erroneous, misguided and a danger to the world. Ban Ki Moon, the UN Secretary-General and a South Korean, said that he was deeply disturbed by the detonation, which was detected by US scientists as a magnitude 4.7 earthquake.

The options to halt Pyongyang’s advanced nuclear programme are extremely limited. A military strike is not possible, given the North’s huge conventional army and close proximity to Japan and South Korea.

China is unlikely to back fresh sanctions. Even Russia spoke only of “concern”. The US has been grappling with the threat of North Korea’s nuclear programme since the early 1990s, but Pyongyang is the world’s most isolated regime and previous measures have done nothing to stop its pursuit of nuclear weapons.

The test is viewed as the ailing Kim Jong Il’s latest attempt to put pressure on Washington for one-to-one talks. North Korea pulled out of six-party talks in April after the UN condemned its launch of a long-range missile.

North Korea is believed to have enough plutonium for at least six atomic bombs. There is growing concern in Washington that it is hell-bent on building one and has advanced so far that it is no longer interested in negotiating away its nuclear technology.

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