The Japanese government reportedly said it will not sign a United Nations statement calling for nuclear weapons to be made illegal.

Sources say Japan refused to sign the statement calling for greater efforts to outlaw nuclear weapons that was drawn up by Switzerland, Norway and 14 other nations during the UN General Assembly.

Japan is said to have refused since its national defense depends greatly on nuclear deterrence, including the U.S.’ nuclear strategy.

Japan’s amended 2010 National Defense Program Guideline states that as long as nuclear weapons exist, the United States’ extended nuclear deterrence is necessary.