Comprehensive Nuclear-Test-Ban
Treaty reaches 100 ratifications


The Comprehensive Nuclear-Test-Ban Treaty has been ratified by 100 States. Mauritania's ratification of the Treaty, deposited with the Secretary-General of the United Nations on 30 April 2003, has brought the tally to 100, marking a significant milestone on the road to Treaty universality. One hundred and sixty-seven States so far have signed the Treaty. The Treaty bans nuclear-weapon test explosions and all other nuclear explosions, in any environment. By constraining both the development and the qualitative improvement of nuclear weapons, it makes an important contribution to global non-proliferation and nuclear disarmament. The proliferation of weapons of mass destruction is unquestionably one of the most alarming security challenges facing the international community. Multilateral arms control and non-proliferation measures play a vital role in ensuring global security and stability. The Treaty has made substantial progress in the seven years since it opened for signature in New York on 24 September 1996. Over 130 States signed it that year, and the flow of signatures has continued steadily ever since. Ratifications have also continued apace, rising noticeably in the years in which conferences on Facilitating the Entry into Force of the Treaty are held. Under the terms of the Treaty, a global verification regime to monitor compliance with the Treaty must be operational by the time the Treaty enters into force. As part of the global verification regime, an International Monitoring System (IMS) which uses state-of-the-art seismic, hydroacoustic, infrasound and radionuclide technologies is being constructed. When complete, the IMS network will consist of 337 monitoring facilities around the world which will monitor the earth continuously for evidence of clandestine nuclear test explosions. IMS facilities are capable of registering vibrations from a possible nuclear explosion underground, in the seas and in the air, and can detect radioactive debris released into the atmosphere. The verification system continues to be steadily and securely developed, and will have the capacity to ensure that non-compliance with the provisions of the Treaty can be detected in a timely manner. Of the 337 IMS facilities around the world (comprising 321 stations and 16 radionuclide laboratories), site surveys for 284 stations, (equivalent to 88% of the total number of sites), are now complete. Altogether 150 stations (47% of the total) have already been built or substantially meet specifications, and 80 additional stations are under construction or in contract negotiations. Some 70 facilities are currently contributing data to the CTBT?s International Data Centre (IDC) in Vienna, where the data are processed and, together with IDC products, released to Member States for final analysis. After installation, stations need to be certified in order to become part of the IMS network. To date, 49 stations and 1 radionuclide laboratory have been certified. To enter into force, the Treaty must be signed and ratified by the 44 States that formally participated in the work of the 1996 session of the Conference on Disarmament and that possess nuclear power or research reactors. Thirty-one of these States have ratified the Treaty. ******************* The 100 States that have deposited their instruments of ratification of the CTBT are: Albania, Argentina, Australia, Austria, Azerbaijan, Bangladesh, Belarus, Belgium, Benin, Bolivia, Botswana, Brazil, Bulgaria, Burkina Faso, Cambodia, Canada, Chile, Costa Rica, Cote d'Ivoire, Croatia, Czech Republic, Denmark, Ecuador, El Salvador, Estonia, Fiji, Finland, France, Gabon, Georgia, Germany, Greece, Grenada, Guyana, Holy See, Hungary, Iceland, Ireland, Italy, Jamaica, Japan, Jordan, Kazakhstan, Kenya, Kiribati, Latvia, Lao People's Democratic Republic, Lesotho, Lithuania, Luxembourg, Maldives, Mali, Malta, Mauritania, Mexico, Micronesia (Federated States of), Monaco, Mongolia, Morocco, Namibia, Nauru, Netherlands, New Zealand, Nicaragua, Niger, Nigeria, Norway, Panama, Paraguay, Peru, Philippines, Poland, Portugal, Qatar, Republic of Korea, Romania, Russian Federation, Saint Lucia, Samoa, San Marino, Senegal, Sierra Leone, Singapore, Slovakia, Slovenia, South Africa, Spain, Sweden, Switzerland, Tajikistan, the former Yugoslav Republic of Macedonia, Turkey, Turkmenistan, Uganda, Ukraine, United Arab Emirates, United Kingdom of Great Britain and Northern Ireland, Uruguay, Uzbekistan and Venezuela.

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Annika Thunborg, Chief, Public Information  
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