America has joined the rest of the world in condemning North Korea for its latest nuclear weapon and missile tests.President Barack Obama said the tests were reckless, and called on the international community to respond. Early on Monday morning, North Korea exploded an underground nuclear device, and test-fired three short-range missiles. Following this recent test of a long-range rocket, tension is rising rapidly. “North Korea is not only deepening its own isolation, it’s also inviting stronger international pressure as was evident overnight, as Russia and China, as well as our traditional alies South Korea and Japan have all come to the same conclusion: North Korea will not find security and respect through threats and illegal weapons,” the president said. His concerns were echoed by Europe. “It’s alarming, it’s a continuation of the provocative behaviour of the regime in Pyongyang,” said the Swedish Foreign Minister Carl Bildt. “I think it further isolates the country, I think it further aggravates the long-term situation of the country, and, of course, it’s not good for the international atmosphere on the Korean peninsula. So it is a most disturbing and alarming development.” Russian scientists measured the explosion, at a base near North Korea’s border with China, at 20 kilotonnes – 20 times more powerful than Pyongyang’s first nuclear test in October 2006. It shows how far the rogue state’s nuclear technology has improved. The UN Security Council meets tonight to consider tougher sanctions. But North Korea is so isolated and reclusive the world may find there is little it can do to end its nuclear ambitions.