Japan has declined to endorse a joint statement against the use of nuclear weapons at a preparatory committee for the next Nuclear Nonproliferation Treaty review meeting.

The statement on the humanitarian impact of the weapons, announced Wednesday by South Africa, urges that atomic weapons never be used under any circumstances. Members of the South African delegation said Japan sought to cut the phrase "under any circumstances."

The government's top spokesman, Chief Cabinet Secretary Yoshihide Suga explained at a news conference Thursday that Japan did not agree with the statement, given "the security environment in which the country is placed."