Large voluntary contribution by the United States

IMS Monitoring Facilities in the United States - click for interactive map.

The United States has pledged a voluntary contribution of up to $25.5 million to the Preparatory Commission for the Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO). The funds will be used to reconstruct hydroacoustic station HA04 in the French Southern Territories. This is the eleventh and last hydroacoustic station to be built as part of the International Monitoring System (IMS). The reconstruction will complete the hydroacoustic network, which monitors the world’s oceans for any sign of a nuclear explosion.


This latest donation is the largest single contribution of its kind to the organization to date and comes only weeks after the United States pledged a voluntary in-kind contribution valued at $8.9 million to the CTBTO. The earlier pledge will underwrite contribution in-kind projects implemented by U.S. agencies in coordination with the CTBTO that support the further development of the full  range of CTBTO verification and monitoring activities to detect nuclear tests, including enhancing radionuclide and noble gas detection technologies, refining seismic detection techniques, and supporting auxiliary seismic stations.

I am extremely grateful to the United States for its generous contribution. These large voluntary contributions are a further demonstration of an outstanding commitment to the CTBTO. CTBTO Executive Secretary Tibor Toth

The United States' support for the work of the CTBTO manifests itself in many different ways. The country is already the largest single regular contributor to the organization's budget. It is also the host of the largest number of International Monitoring System facilities - 39 of a total of 337, of which 36 facilities are certified. The United States voluntarily assumes the operation and maintenance costs for all facilities on its territory. In addition, a large number of U.S. experts participate actively in the CTBTO's policy-making organs, workshops and seminars.

U.S. Secretary of Energy Steven Chu and NNSA Administrator Tom D’Agostino visited the CTBTO on 21 September 2010.

While the CTBT has been signed by 182 and ratified by 154 of them (see map), it needs to be ratified by all 44 States identified as nuclear technology holders to enter into force. Of these, nine have yet to deposit their instrument of ratification: China, the Democratic People's Republic of Korea, Egypt, India, Indonesia, Iran, Israel, Pakistan and the United States.