Secret pacts on nuclear arms and other issues were reached between Japan and the United States during the Cold War, a Foreign Ministry panel concluded March 9, effectively ending the government's decades-long official denial.

U.S. Ambassador to Japan Edwin O. Reischauer meets Foreign Minister Masayoshi Ohira in April 1963 and the two reportedly confirmed a secret pact allowing U.S. Navy ships to carry nuclear weapons into Japanese ports. KYODO PHOTO

While the pacts have already been exposed through U.S. declassified documents and other sources, the panel's investigation, launched after the Democratic Party of Japan's historic rise to power last year, made clear that previous governments led by the ousted, but long-ruling, Liberal Democratic Party were "dishonest" about the issue, and raised questions over the management and disclosure of diplomatic papers.

Among the pacts the panel acknowledged was "a tacit agreement" that emerged during the 1960 revision of the Japanese-U.S. security treaty that led to Tokyo effectively allowing port calls by U.S. vessels carrying nuclear weapons without prior consultation.

Foreign Minister Katsuya Okada said March 9 that he cannot rule out that nuclear weapons were brought into Japan under the secret pacts.

Officially, Washington was supposed to consult with Tokyo beforehand when bringing nuclear weapons into the country, due to strong anti-nuclear sentiment among the Japanese public.

With the details of the bilateral security arrangements finally brought to light from the Japanese side in the form of about 330 newly declassified documents, the panel revealed that the country's non-nuclear principles of not possessing, producing or allowing nuclear weapons on its territory were a sham.