Japan's Chief Cabinet Secretary says the recent US subcritical nuclear test is not prohibited by a UN test ban treaty because it did not produce a nuclear explosion.
Yoshihide Suga told reporters on Monday that a discussion is needed on how to deal with such tests while pursuing nuclear disarmament. He said Japan aims for a world without nuclear weapons.
Suga was commenting on the announcement by the US Department of Energy's Lawrence Livermore National Laboratory that it carried out a subcritical nuclear test in Nevada in February.
Suga said he understands that the experiment did not involve a nuclear explosion, which is prohibited under the Comprehensive Nuclear Test Ban Treaty.
He said Japan places importance on having the treaty take effect as a specific step in pushing for nuclear disarmament.
Suga said that should be the initial goal to achieve.
He went on to say the issue of subcritical and other tests that do not produce nuclear explosions should be discussed as part of the efforts to pursue nuclear disarmament.