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Verification of Nuclear Arms Control and Disarmament Treaties


Verification refers to the process of collecting and analyzing information to determine compliance with treaty stipulations.  Information is usually collected by experts who draw conclusions based on the evidence collected and pass it on to a higher political body for judgment.  This process ultimately establishes a system of trust and confidence building among treaty members that stipulations are being adhered to completely and no cheating is taking place – in short, that all members are in compliance with the treaty. 

In nuclear arms control and disarmament treaties, these stipulations relate to the nonproliferation of nuclear weapons, the reduction of nuclear stockpiles, and the prohibition of research and testing. 

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Why Is Verification Important?

The ability to verify treaty compliance gives meaning to international arms control and disarmament treaties.  An effective verification mechanism enhances the purpose and goals of the treaty because it ensures that treaty requirements are actually implemented by each member state.  Effective verification can also serve as an incentive for countries to sign and ratify treaties, and may deter members from cheating or simply partially fulfilling treaty obligations.  Ideally, verification takes place in a timely manner before the violation of a treaty becomes a threat to the national security of other treaty members. 

How Does Verification Work?

Verification efforts can be carried out in several different ways by single states or collectively.  In case of the Comprehensive Test Ban Treaty (CTBT), an organization called the Comprehensive Test Ban Treaty Organization (CTBTO) external link, headquartered in Austria, is mandated with the creation of a global verification system.  The CTBTO relies on remote monitoring through seismic technologies.  Other treaties such as the nuclear Non-Proliferation Treaty (NPT) employ trained professionals that conduct on-site inspections of member states’ nuclear facilities and materials.  These inspections, also called safeguards external link, take place under the auspices of the International Atomic Energy Agency (IAEA) external link in Vienna and determine whether a country is diverting peaceful nuclear technologies for military purposes.   

Role of the United Nations

Various United Nations bodies and institutions are involved in verification matters. 

  • The United National General Assembly passes non-binding resolutions and initiates studies external link on verification and compliance.  
  • The Conference of Disarmament (CD) in Geneva negotiates disarmament treaties such as the CTBT and accompanying verification arrangements.  In 1995, the CD mandated external link the commencement of negotiations on a verifiable fissile material cut-off treaty. 
  • The United Nations Disarmament Commission (UNDC) discusses disarmament and verification issues.  In 1988, the UNDC published the pdf document 16 Principles of Verification.
  • The United Nations Security Council (UNSC) adopts binding measures on disarmament, established external link the United Nations Monitoring, Verification, and Inspection Commission (UNMOVIC)and imposes sanctions in case of non-compliance.   

International Verification Bodies and Regimes

Verification mechanisms are often implemented through an institution specifically created for monitoring a treaty.  These verification bodies usually depend on the financial and political support of the member states of the treaty.  

The main nuclear arms control and disarmament treaties that come with a verification mechanism are the nuclear Non-Proliferation Treaty (NPT) and the Comprehensive Test Ban Treaty (CTBT).

International Atomic Energy Agency (IAEA):
The International Atomic Energy Agency (IAEA) external link was created in 1957 to promote the exchange of nuclear technology between countries and verify the peaceful application of such technology. 

The Statute of the IAEA authorizes the Agency to conduct safeguards activities external link that serve as a verification mechanism “to ensure that special fissionable and other materials, services, equipment, facilities, and information made available by the Agency or at its request or under its supervision or control are not used in such a way as to further any military purpose.”  Safeguards may also apply to bilateral or multilateral agreements between countries. 

The nuclear Non-Proliferation Treaty (NPT) of 1969 requires its non-nuclear weapon members to enter into a comprehensive safeguards agreement with the IAEA.  The NPT prohibits the use of peaceful nuclear technology for nuclear weapons production.  To ensure that peaceful technology is not diverted, NPT states have to declare facilities and materials to the IAEA.  Safeguards are the verification mechanism by which the IAEA can establish whether the state’s declared facilities and materials are used for peaceful purposes only. 

After the discovery of Iraq’s clandestine nuclear weapons program in the early 1990s, IAEA safeguards activities were broadened to improve the Agency’s ability to detect undeclared nuclear material and nuclear weapon-related activities.  The Additional Protocol requires States parties to report on all aspects of its nuclear fuel cycle, allow for short-notice inspections to all facilities on a nuclear site and access to other nuclear-related sites.  This effort to strengthen the IAEA verification system allows for more intrusive inspections so that the IAEA can not only verify the presence of declared material but also detect undeclared facilities and materials. 

The IAEA trains its own inspectors, who usually have professional expertise in nuclear physics, chemistry or engineering.  Inspectors visit nuclear facilities in member countries, where they conduct a range of activities, including the collection of environmental samples in facilities and the verification of design information of facilities as provided by the host country.  Verification also includes the remote monitoring of movement of declared material in a facility, the evaluation of information derived from a country’s official declaration and open source information.

Even though safeguards are a treaty requirement under Article III of the NPT, not all member states have concluded their agreements with the IAEA.  Most of these countries, such as Benin, Somalia, or Timor-Leste, are not engaged in any nuclear activities and do not see the need for IAEA inspections on their territory.  The Additional Protocol is currently a voluntary measure, which means that NPT member states are not obligated to implement it.  The IAEA and many NPT members are pushing for the universalization of the Additional Protocol to make it the new safeguards standard of today. 

United Nations Monitoring, Verification, and Inspection Commission (UNMOVIC)
Iraq’s secret nuclear weapon activities, which started in the early 1970s, remained undetected by IAEA safeguards until the 1991 Gulf War.  After the war, the United Nations Security Council set up the United Nations Special Commission (UNSCOM) external link to dismantle the Iraqi nuclear program in cooperation with the IAEA.  The IAEA created a country-specific verification system under the IAEA Iraq Action Team, which removed all nuclear weapons-grade material and destroyed nuclear sites during the 1990s.  The Action Team was renamed the Iraq Nuclear Verification Office (INVO) external link in December 2002. 

These verification operations came to a halt in 1998, resumed in 2000 and were disrupted again in 2003 prior to the US-led invasion of Iraq.  At that time, IAEA Director General ElBaradei announced external link that the IAEA had not found “evidence or plausible indication of the revival of a nuclear weapons program in Iraq.”

Since the end of the war in Iraq, the IAEA has been unable to return its inspectors for safeguards inspections.  Verification work continues through the analysis of open source information, and the INVO remains ready to resume its work as soon as possible. 

CTBTO Preparatory Commission:
The Comprehensive Test Ban Treaty (CTBT) of 1996 bans all nuclear explosions.  The CTBT has not entered into force yet because it still requires the ratification of certain countries, including China, Iran, Israel and the United States.  Current signatories formed the Preparatory Commission for the Comprehensive Test Ban Treaty Organization external link to facilitate the entry into force of the treaty. 

The CTBTO establishes the International Monitoring System (IMS) and International Data Center, which form the basis of the verification system.  The purpose of the CTBTO work is to ensure that the verification mechanism is fully developed by the time the CTBT enters into force.  The IMS comprises an international network of 321 monitoring stations and 16 radionuclide laboratories which monitor the earth for evidence of nuclear explosions in all environments. The system uses four verification methods: seismic, hydroacoustic, infrasound, and radionuclide stations, and will be supplemented by on-site inspections once the treaty is in force.

Regional Verification Arrangements

Agency for the Prohibition of Nuclear Weapons in Latin America and the Caribbean
The Agency for the Prohibition of Nuclear Weapons in Latin America and the Caribbean (OPANAL) external link works to ensure the implementation of the Treaty for the Prohibition of Nuclear Weapons in Latin America and the Caribbean, also called the Treaty of Tlatelolco.  The Treaty of Tlatelolco of 1967 establishes a regional nuclear-weapon-free zone and prohibits the testing, use, fabrication, production, or acquisition of nuclear weapons by its 33 member states.

On 26 August 1992, OPANAL's General Conference approved amendments to Treaty Articles 14, 15, 16, 19, and 20, which strengthened the existing verification mechanism.  According to the amendments, the IAEA is the only organization that has the power to carry out special inspections if invited by a member state to the Treaty. 

Brazil-Argentine Agency for Accounting and Control of Nuclear Materials (ABACC)
The Brazil-Argentine Agency for Accounting and Control of Nuclear Materials (ABACC) external link was set up under a 1991 bilateral agreement between Brazil and Argentina for the peaceful use of nuclear energy.

ABACC monitors the peaceful use of nuclear energy in Brazil and Argentina, and ensures that no technology is misused for military purposes using the Common System for Accounting and Control of Nuclear Materials (SCCC).  The SCCC is a set of safeguards procedures applicable to all nuclear materials used in all nuclear activities carried out in Brazil and Argentina to timely detect the diversion of any significant quantities of nuclear materials. Under the 1991 agreement, Brazil and Argentina are obliged to submit to the SCCC all nuclear materials used in all nuclear activities carried out within their respective territories, or under their jurisdiction or control.

Safeguards involve material accounting, which includes tracking the movement of materials, examination of declared information, on-site inspections and the assessment of information collected by inspectors.  These regional safeguards are complemented by IAEA safeguards under the Quadripartite Agreement between Brazil, Argentina, the ABACC, and the IAEA. The Quadripartite Agreement entered into force in 1994.


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