Japanese Defense Minister Shinjiro Koizumi on Tuesday again called for discussions on reviewing the country’s Three Non-Nuclear Principles and expressed support for considering the introduction of nuclear-powered submarines, Kyodo News reported.

Speaking at a seminar in Tokyo, Koizumi said an environment should be created in which necessary security policies can be discussed openly and frankly without prejudice, and that as Japan revises its three key security documents by the end of the year, society as a whole should develop a shared understanding of nuclear threats. The Three Non-Nuclear Principles stipulate that the country will not possess, produce or permit the introduction of nuclear weapons, and the current National Security Strategy explicitly states that the policy will remain unchanged. Prime Minister Sanae Takaichi told parliament in October that her government would “deepen concrete and realistic considerations” regarding the potential introduction of nuclear-powered submarines for the Self-Defense Forces.