"If Japan were to go for nuclear weapons we would have to look at South Korea, Taiwan and eventually everybody in the region" also possibly acquiring atomic arms, he added.

"I always look at Japan as a torch holder for nuclear disarmament," ElBaradei said, adding that Japan's history as the only country to have been attacked with nuclear weapons meant it had a "moral responsibility".

ElBaradei added, however, that he had been assured by Japanese government officials that Tokyo had no intention of abandoning its long standing policy against nuclear weapons.

On Thursday ElBaradei met with Foreign Minister Taro Aso, who last week said Japan was able to produce nuclear weapons if it chose to do so.

Prime Minister Shinzo Abe has ruled out even discussing building nuclear weapons, but the issue has caused concern in neighboring countries haunted by Japan's past aggression.

Japan is the only country to have suffered a nuclear attack. US nuclear bombs obliterated the Japanese cities of Hiroshima and Nagasaki in the closing days of World War II, killing more than 210,000 people.

Related Links
International Atomic Energy Agency
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