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The NSG Decision on Sensitive Nuclear Transfers: ABACC and the Additional Protocol
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David S. Jonas, John Carlson, and Richard S. Goorevich

On a windy day in June 2011, near the shores of the Dutch village of Noordwijk, representatives of the 46 countries that make up the Nuclear Suppliers Group (NSG) agreed on a much-discussed revision of the section of the group’s guidelines covering exports relating to uranium enrichment and spent fuel reprocessing.

The agreement was a vivid example of NSG efforts to promote nonproliferation without unduly restricting nuclear commerce. Coming after seven years of intensive internal debate, the accord illustrated the difficulty of gaining the support of all members of the group, which operates by consensus.

Because of ongoing discussion in the media and nongovernmental organizations (NGOs) and to avoid any possible misunderstandings in the discussions leading up to 2015 Nuclear Nonproliferation Treaty (NPT) Review Conference, it is timely to review the background and basis for the NSG decision.

The NSG guidelines were designed to apply a higher standard to controls on transfers of enrichment and reprocessing equipment, material, and technology than to other nuclear exports. Paragraph 6 of the guidelines stated simply that suppliers should “exercise restraint” on enrichment- and reprocessing-related exports, which are particularly sensitive because of their potential use in producing material that can be used in nuclear weapons. The revised guidelines spell out more specifically what the elements of that restraint should be. A key challenge for the NSG had been to find appropriate language to capture what had been the practice of suppliers in a way that non-NSG governments and the general public could understand.

Since the Noordwijk decision, most of the discussion of the NSG’s action has centered on a specific reference to the requirement for safeguards in Paragraph 6(c):

suppliers should authorise transfers, pursuant to this paragraph, only when the recipient has brought into force a Comprehensive Safeguards Agreement, and an Additional Protocol based on the Model Additional Protocol or, pending this, is implementing appropriate safeguards agreements in cooperation with the IAEA [International Atomic Energy Agency], including a regional accounting and control arrangement for nuclear materials, as approved by the IAEA Board of Governors.

This language expresses the NSG’s agreement that the increased proliferation risk associated with these technologies warranted greater mitigation efforts. The group also looked to the IAEA effort to increase the standard of safeguards through the introduction of the Model Additional Protocol and concluded that it would be appropriate to consider implementation of a protocol as a condition of supply. Since the 1990s, it has been generally recognized that the IAEA’s comprehensive safeguards agreement—the agreement that applies to non-nuclear-weapon states under the NPT—does not adequately cover the detection of undeclared nuclear activities. The Model Additional Protocol addresses this by extending the access available for inspectors and the information to be provided to the IAEA.

Under the Noordwijk language, the safeguards standard for enrichment- and reprocessing-related transfers goes above and beyond the requirements previously enumerated in the guidelines and allows for flexibility in its application. Although the NSG text makes explicit reference to a comprehensive safeguards agreement and an additional protocol, it also allows for the concern for higher risk mitigation to be addressed by a regional accounting and control arrangement that has been approved by the IAEA, pending the ultimate implementation of an additional protocol.

The new language sparked a debate, particularly in the press and among NGOs, over whether a regional arrangement such as the Brazilian-Argentine Agency for Accounting and Control of Nuclear Materials (ABACC) is equivalent to a comprehensive safeguards agreement with an additional protocol. As this article will demonstrate, the new language does not say that and was not intended to do so. By considering the legal and safeguards aspects of the ABACC arrangements and an additional protocol, the article will demonstrate that the two measures are meant for different purposes but that they both provide a higher level of confidence than a comprehensive safeguards agreement alone that exported enrichment and reprocessing technologies will be used only for peaceful purposes. The article therefore concludes that both meet the nonproliferation requirements of the revised NSG guidelines.

Legal Considerations

Treaties ordinarily may neither impose obligations on nor create legal entitlements for third states. The starting point for analysis is that treaty rights and obligations are legally confined to the contracting parties.[1]

Neither Brazil nor Argentina has signed an additional protocol with the IAEA. The two countries, however, work together under a strict model of safeguards inspections and other measures organized by ABACC. On December 13, 1991, Argentina, Brazil, ABACC, and the IAEA signed an agreement known as the Quadripartite Agreement, which consolidates the system for the application of the safeguards that are in force in both countries, providing for joint inspections by the IAEA and ABACC, involving personnel from both countries. Brazil has argued that this mutual inspection aspect of ABACC provides for a higher level of assurance than a comprehensive safeguards agreement and is a reason not to sign an additional protocol.

Specifically, Brazil claims that an additional protocol discriminates against NPT non-nuclear-weapon states by creating more-intrusive requirements for their nuclear programs while nuclear-weapon states are not properly fulfilling their disarmament pledges under Article VI of the treaty. Brazil also maintains that an additional protocol would create unnecessary financial burdens and stifle commercial nuclear development by creating new regulations.[2] Others argue that a regional arrangement such as the Quadripartite Agreement does not meet the objectives of an additional protocol and consequently cannot be considered as a substitute for it.

Neither Brazil nor Argentina suggests that the Quadripartite Agreement is a replacement for an additional protocol. Rather, they claim that the higher level of assurance provided under that agreement, particularly through mutual inspections, should be sufficient to meet any international concern as to whether nuclear activities in either state are for peaceful purposes.

Both ABACC and the Model Additional Protocol are intended, in a very general sense, to build confidence that nuclear activities are peaceful, but the two are not the same. The protocol is a legal document setting out rights to additional information and access by IAEA inspectors as a complement to safeguards under the relevant safeguards agreement, while ABACC is an institutional arrangement[3] created with the objective of administering and implementing the Common System of Accounting and Control of Nuclear Materials (SCCC).[4] The purpose of the SCCC is to verify that nuclear material held by the parties is not diverted to nuclear weapons or explosives.

The Quadripartite Agreement is a “full scope safeguards agreement, similar to INFCIRC/153 model agreements,”[5] which are the standard NPT safeguards agreement for non-nuclear-weapon states, now referred to as a comprehensive safeguards agreement. To put it another way, ABACC is a regional organization broadly similar to Euratom. ABACC implements safeguards jointly with the IAEA, with the latter responsible for ensuring that international safeguards requirements are met.[6]

Safeguards Considerations

Under the NPT, non-nuclear-weapon states commit to accepting IAEA safeguards to verify that they are not diverting nuclear material to use in weapons. They agree to accept IAEA safeguards on all nuclear material. An important aspect of this is that these states should not possess undeclared nuclear material. The Model Additional Protocol was developed to address weaknesses in safeguards implemented under comprehensive safeguards agreements. The protocol strengthens the IAEA’s ability to detect undeclared nuclear activities by establishing additional requirements for reporting information and extending IAEA rights of access to various locations in a state. By agreeing to an additional protocol, a state provides the IAEA with specific rights to a wealth of information that is outside the purview of comprehensive safeguards agreements, particularly the right to access locations where no nuclear material is declared to be located.[7]

The Model Additional Protocol permits “complementary access,” a new category of inspector access somewhere between special inspections and routine inspections, for which the IAEA may request access to undeclared locations to conduct verification activities such as environmental sampling.[8] The Quadripartite Agreement, in contrast, is similar to standard comprehensive safeguards agreements and does not provide the IAEA with rights to inspect undeclared locations, other than in the particular circumstances of a special inspection. Thus, an additional protocol goes beyond the Quadripartite Agreement by providing the IAEA with additional measures for ensuring the absence of undeclared activities.[9]

The IAEA emphasizes that, in a state without an additional protocol in force, the agency is unable to provide credible assurance of the absence of undeclared nuclear material and activities. This is reflected in the IAEA’s annual safeguards conclusions. For states with a comprehensive safeguards agreement but no additional protocol, the IAEA is able to conclude only that declared nuclear material has remained in peaceful activities, but not that all nuclear material remained in peaceful activities. This is the safeguards conclusion the IAEA reaches for both Argentina and Brazil. In effect, the IAEA is unable to conclude that states without an additional protocol are fully meeting their NPT peaceful-use commitments.


Because Argentina and Brazil did not accede to the NPT until 1995 and 1998, respectively, the 1991 Quadripartite Agreement and the ABACC arrangements have historical importance in building confidence between the two countries that neither was pursuing a nuclear weapons program, which in itself is a worthwhile achievement

The ABACC arrangements, however, do not provide the standard of assurance expected by the international community. Only the IAEA can provide this standard of assurance and only if the agency is able to implement its full suite of verification activities. As parties to the NPT, Argentina and Brazil are obligated to accept IAEA safeguards procedures necessary to establish that they have placed all nuclear material under safeguards. Under their comprehensive safeguards agreements, they have accepted that the IAEA has the right and the obligation to verify the fulfillment of this obligation.

One must assume that the 46 governments of the NSG that came to agreement in Noordwijk understood and recognized the differences between ABACC and the Model Additional Protocol. Therefore, one must assume that the NSG did not intend to refer to both instruments in the NSG guidelines as a means of comparing them. Rather, the purpose must have been to note that, in defining “restraint” in the transfer of sensitive nuclear technologies, there needed to be the highest level of confidence that there would be no misuse of the facilities involved. As discussed above, the Model Additional Protocol is concerned with the possibility of unknown—that is, undeclared— facilities. In its Noordwijk decision, the NSG indicated that if enrichment and reprocessing equipment and technology were supplied to Argentina and Brazil under current circumstances, NSG members would have confidence that the items would not be misused.

The NSG is not claiming that any comprehensive safeguards agreement is sufficient for NSG purposes. Rather, the distinctive element of the Quadripartite Agreement that swayed the NSG is the joint (mutual) arrangements under ABACC and the SCCC for implementing the agreement. The NSG has accepted ABACC’s claim that these mutual arrangements provide a higher level of assurance than IAEA comprehensive safeguards by themselves. Yet, the NSG has not accepted the idea that these arrangements are as strong as an additional protocol.

The Quadripartite Agreement and the arrangements for implementing the agreement do not directly address the issue of possible undeclared activities; they address the issue only indirectly through the increased level of confidence the parties have from the agreement. In other words, in the particular case of Argentina and Brazil, the NSG was comfortable that ABACC and the Quadripartite Agreement provided assurances that enrichment and reprocessing facilities were not being misused for nuclear weapons purposes, given that Argentina and Brazil already possessed enrichment and reprocessing technology and there had been no problems or issues raised throughout the history of the agreement. Yet, the NSG text also signals that there is not necessarily the same level of confidence about any similar arrangements that might arise in the future. In this regard, there has not been any call for such arrangements, as some had envisioned when the NSG agreed to this language.

Whether NSG members would make the same judgment with another type of regional agreement that did not reach the Model Additional Protocol standard and did not have this robust history remains to be seen. This is especially important in the case of states that have established capabilities in enrichment and reprocessing. The use of the phrase “pending this” in the NSG decision links the concepts of the Model Additional Protocol and ABACC as an expression of hope that comfort with the ABACC arrangement will be bolstered in due course by the conclusion of additional protocols by both countries or at least the adoption of the key elements of the protocol that provide the highest level of confidence. Ultimately, the NSG did what it intended to do seven years prior to Noordwijk, which is to define “restraint.” It defined a safeguards standard that provided this highest level of confidence, which is the Model Additional Protocol, but also took into account the confidence that has been generated by years of safeguards implementation by ABACC.



David S. Jonas is general counsel of the Defense Nuclear Facilities Safety Board and a former general counsel of the Department of Energy’s National Nuclear Security Administration (NNSA). John Carlson is a counselor for the Nuclear Threat Initiative (NTI) and former director-general of the Australian Safeguards and Non-Proliferation Office. Richard S. Goorevich is a senior policy adviser for nuclear fuel cycle and regulatory issues in the NNSA and chairman of the Nuclear Suppliers Group Consultative Group. The views expressed in this article are those of the authors and do not necessarily reflect the views of the U.S. government or the NTI.




1. “Vienna Convention on the Law of Treaties,” May 23, 1969, Treaty Series: Treaties and International Agreements Registered or Filed and Recorded With the Secretariat of the United Nations, Vol. 1155, art. 34. See Anthony Aust, Handbook of International Law (New York: Cambridge University Press, 2005), p. 97; Luke T. Lee, “Law of the Sea Convention and Third States,” American Journal of International Law, Vol. 77 (1983): 541, 544

2. Andrea Viski, “The Revised Nuclear Suppliers Group Guidelines: A European Union Perspective,” EU Non-Proliferation Consortium Non-Proliferation Papers, No. 15 (May 2012), p. 8, www.sipri.org/research/disarmament/eu-consortium/publications/nonproliferation-paper-15.

3. Ibid.

4. The Quadripartite Agreement refers to ABACC as “the legal person created by the SCCC Agreement.”

5. Marco Marzo et al., Regional Safeguards Arrangements: The Argentina-Brazil Experience, IAEA-SM-346/113, 1997, p. 2, www.abacc.org.br/artigos_antigos/iaea-sm-346-113.pdf.

6. Marco Marzo, “ABACC: Designing and Implementing Bilateral Inspections in Argentina and Brazil” (presentation at conference entitled “Argentina and Brazil: The Latin American Nuclear Rapprochement,” Nahel Soreq, Israel, May 16, 1996), http://isis-online.org/596pm1.

7. On access to undeclared locations, see International Atomic Energy Agency, “Model Protocol Additional to the Agreement(s) Between State(s) and the International Atomic Energy Agency for the Application of Safeguards,” INFCIRC/540 (Corrected), September 1997, arts. 4a(ii), 5b, 5c. On access to known sites where no nuclear material has been declared to be located, see ibid., arts. 4a(iii), 5a(iii).

8. UN Institute for Disarmament Research and Verification Research, Training and Information Centre, “Coming to Terms With Security: A Handbook on Verification and Compliance,” UNIDIR/2003/10, 2003, pp. 64-65.

9. U.S. Department of State, “United States Information Pertaining to the Treaty on the Non-Proliferation of Nuclear Weapons,” 2010, www.state.gov/documents/organization/141928.pdf.