Comprehensive Test Ban Treaty (CTBT)
The CTBT bans all nuclear weapon test explosion or any other nuclear explosions. The Treaty was negotiated in Geneva by the Conference on Disarmament, was adopted by the General Assembly as resolution A/RES/50/245 on 10 September 1996, and opened for signature in September 1996. However, it has not yet entered into force.
All forty-four members of the Conference on Disarmament with nuclear power and/or research reactors must sign and ratify the Treaty before it enters into force; they are listed in Annex II of the Treaty. The Treaty will enter into force 180 days after the ratification by all states listed in Annex 2 to the Treaty. Out of the 44 Annex II states, eight have not yet ratified the CTBT: China, the Democratic People’s Republic of Korea, Egypt, India, Iran, Israel, Pakistan, and the United States. Three countries—India, Pakistan, and the Democratic People’s Republic of Korea—have tested nuclear explosive devices since the CTBT was negotiated. And since then, the United States has carried out over 20 subcritical nuclear tests at its Nevada Test Site.
The Treaty is intended to stop the qualitative nuclear arms race. Unfortunately, the CTBT does not prohibit research on nuclear weapons, including subcritical tests. But the Treaty's stated objectives are disarmament and the prevention of further nuclear weapon modernization and subsequent arms races.