North Korean military honour guard standing to attention at Pyongyang’s airport during a diplomatic visit. Photograph: Stephen Shaver/AFP/Getty Images North Korea today risked further international isolation after it claimed to have successfully tested a nuclear weapon as powerful as the atomic bomb that destroyed Hiroshima. The test comes less than two months after the North enraged the US and its allies by test firing a long-range ballistic missile. The KNCA news agency, the regime’s official mouthpiece, said: ‘We have successfully conducted another nuclear test on 25 May as part of the republic’s measures to strengthen its nuclear deterrent.’ Officials in South Korea said they had detected a tremor consistent with those caused by an underground nuclear explosion. The country’s Yonhap news agency reported that the North had test-fired three short-range missiles from a base on the east coast immediately after the nuclear test. The underground atomic explosion, at 9.54am local time (0154 BST), created an earthquake measuring magnitude 4.5 in Kilju county in the country’s north-east, reports said. President Barack Obama called the test a matter of grave concern to all countries. ‘North Korea is directly and recklessly challenging the international community,’ he said […]