'It is certainly the case that Japan has the capability to possess nuclear weapons, but has not made them,' Mr Hata told reporters at the Diet (parliament) building. His comment, at a time of tension over North Korea's suspected nuclear programme, reverses a 50-year taboo in the only country to have suffered a nuclear attack, and is likely to cause furious protest inside Japan and in North Korea.
Japan, which has large stockpiles of plutonium and a high level of technological expertise, has long been presumed by outsiders to be capable of building a nuclear weapon. But until yesterday no government official, not to speak of the Prime Minister, has dared to admit that Japan was capable of going nuclear. Tokyo has repeatedly said it would abide by its so-called 'three noes' policy: not to possess, manufacture or introduce nuclear weapons on to its territory. Earlier this year the Independent was denounced in Foreign Ministry press briefings for suggesting that Japan could build a nuclear bomb and supply it with its own missiles.
One of the greatest fears surrounding North Korea's secretive nuclear programme is that it could provoke a regional response - with Japan, South Korea and Taiwan seeking to develop nuclear weapons and starting an even more deadly and unstable arms race than that between the United States and the former Soviet Union. Mr Hata's comments yesterday show how quickly such a prospect could develop if efforts to force North Korea to abandon any nuclear weapons programme it has, and to prove this to its neighbours by allowing full international inspections, are not successful.
Mr Hata was asked in a parliamentary committee meeting by an opposition MP if Japan should confirm to 'other nations' that it can indeed produce nuclear weapons, but refrained from so doing for political reasons. Mr Hata said he 'agreed absolutely' that that was the case. The North Korean nuclear threat has split the Japanese parliament, with conservatives calling for a tough approach to sanctions, while the Socialists repeat their decades-old policy of friendship with the dictatorship of Kim Il Sung.
After the committee meeting, journalists asked Mr Hata to confirm his unprecedented remarks, which he did. Later, however, the chief cabinet secretary, Hiroshi Kumagai, softened the effect of the Prime Minister's words. 'It is not true that Japan is developing nuclear weapons,' said Mr Kumagai. 'Japan limits its use of nuclear energy for peaceful purposes, abstains from military utilisation, and does not try to possess nuclear-weapons technology or knowhow.'
More than 100,000 people were killed in Hiroshima and more than 70,000 in Nagasaki by the atomic bombs dropped by the US in August 1945. Since then, Japanese politicians have used the horrors of Hiroshima and Nagasaki to underline their country's 'peace constitution', which renounces war and the use of force to settle international disputes.
Mr Hata has said his government will support the US call for sanctions against North Korea in the UN Security Council. But the Socialist Party, which holds the balance of seats, opposes them.