Japan warns that it will attack if North Korea aims missile

Japan's Defence Minister has stressed his country's right to strike North Korean missile sites if an attack is thought imminent.

In an exclusive interview, Shigeru Ishiba told The Independent: "The Japanese constitution permits my position. Attacking North Korea after a missile attack on Japan is too late. If North Korea orders its military to send a missile to attack Japan and the missile is raised to vertical in preparation for launch, then Japan will assume that an attack has begun and has the right to attack that particular missile launch site. What else can the missile be used for but to attack us?"

Intelligence officials estimate that North Korea has at least 100 Rodong ballistic missiles capable of striking Japan.

Mr Ishiba said: "The threat from North Korea, however, is not just aimed at Japan and the US, it's a problem for the whole world." He insisted his position was a defensive one. The tension was the fault of Pyongyang, he said, for "continuing to develop weapons in violation of their promises. We're just defending ourselves."

Japan is planning to develop a new type of radar to improve its ability to monitor North Korea's missile development, the Kyodo news agency reported yesterday.

The hawkish Mr Ishiba, who has earned a reputation for pushing the limits of Japan's debate on defence since taking office almost a year ago, has made clear he favours a much tougher stance than his predecessors toward Japan's Stalinist neighbour.

He believes that President George Bush's strategy is closer to his own approach, than the strategy of Bill Clinton. "Clinton's policy toward North Korea was based on two false premises: one, that Pyongyang would keep its promises [regarding the 1994 agreement to abandon its nuclear programme]; and two, that North Korea would collapse," he said.

"North Korea neither kept its promises nor collapsed. We are now faced with the consequences."

Earlier this year Mr Ishiba sparked a huge row when he told parliament that it was "worth considering" whether Japan should have an offensive capability, raising the possibility of radical change to its 50-year-old pacifist constitution, which renounces war "for ever". The prospect of a newly aggressive Japan, which already boasts annual military expenditure of almost £25bn - 25 per cent larger than Britain's - worries its neighbours, who have bitter memories of the Second World War.

Mr Ishiba's statements are another sign that Japan is slowly but inexorably moving away from a defence posture that many conservatives view as outdated in the aftermath of the Cold War. A number of senior politicians have recently floated the idea of Japan developing its own nuclear weapons, and in June, a bipartisan defence group of 103 junior politicians called for the government to change its defence-only policy to allow for a "minimum" level of offensive capability to attack an enemy. Under recent legislation, Japanese troops can be sent to Iraq to offer medical and reconstruction assistance, in violation, opponents say, of the constitution.

The Prime Minister, Junichiro Koizumi said yesterday that he wanted permanent changes to Article 9 - the section that renounces Japan's right to wage war - which would give the government authority to contribute troops to any international peacekeeping operations. The attack on the Baghdad offices of the UN delayed the dispatch of Japanese troops but Mr Ishiba insisted they would go "when we can ensure their safety". He said: "People are afraid of Japanese troops being killed but war is not a tea party."