U.S. President Donald Trump has approved the U.S.-Saudi Arabia Agreement for Cooperation Concerning Peaceful Uses of Nuclear Energy, commonly known as the "123 Agreement." On July 22, the U.S. Department of Energy announced that the energy ministers of the two countries had signed the 123 Agreement and a separate Bilateral Safeguards Agreement. The U.S. government explained that the agreement would enable billions of dollars in nuclear cooperation over the coming decades while contributing to U.S. nuclear exports, job creation, energy security, and nuclear nonproliferation.

A definitive assessment of the 123 Agreement will only be possible after the text of the agreement, the nonproliferation assessment, and the confidential side letters are made public. Nevertheless, even the information disclosed by the media so far suggests that the agreement is likely to have significant repercussions for the United States, South Korea, and the broader international community. South Korean experts and media outlets tend to argue that U.S. approval of Saudi Arabia's acquisition of enrichment and reprocessing capabilities will strengthen South Korea's position in its negotiations with the United States over the introduction of such capabilities. At present, however, it is difficult to determine whether the Saudi case will ultimately benefit or disadvantage South Korea. This article outlines the main provisions of the Saudi 123 Agreement disclosed to date, examines the background to the exceptional treatment granted to Saudi Arabia, and assesses how the Saudi case may affect South Korea's negotiations with the United States.

| The Substance of the U.S.-Saudi Agreement and the Retreat from the "Gold Standard"

The central feature of the agreement is not that it immediately authorizes Saudi Arabia to enrich uranium, but that it establishes a conditional process through which enrichment could eventually be permitted. According to media reports, the United States and Saudi Arabia will jointly examine the economic and technical feasibility of domestic uranium enrichment in Saudi Arabia for about two years. If the two countries agree that enrichment is necessary and economically viable, U.S. companies may construct enrichment facilities in Saudi Arabia. These facilities are likely to operate under a so-called "black box" arrangement designed to prevent Saudi personnel from gaining direct access to centrifuge designs and other key technologies.

If the feasibility study produces a negative result, however, the enrichment project will not proceed. The agreement also reportedly includes a provision under which Saudi Arabia will refrain for the next ten years from independently pursuing enrichment or cooperating with other countries, such as Russia or China.

Even if the 123 Agreement enters into force and the joint study concludes that enrichment technology may be exported to Saudi Arabia, implementation is expected to take considerable time. Follow-on agreements will be required regarding the ownership and operational control of the enrichment facility, the scope of access granted to U.S. and Saudi technicians, permitted enrichment levels and production volumes, the storage and use of enriched uranium, physical protection, cyber security, and procedures for suspending operations and recovering nuclear materials in the event of a violation. Separate approval under the U.S. Department of Energy's Part 810 regulations governing nuclear technology assistance will also be required, along with export licenses for nuclear materials and equipment. The 123 Agreement is a legal document that opens the door to cooperation, not one that grants blanket authorization for the transfer of enrichment technology.

South Korea also established procedures for introducing enrichment under the revised U.S.-ROK Nuclear Cooperation Agreement concluded in 2015. However, no progress has been made to date because of the lack of cooperation from the United States side. In light of this experience, Saudi Arabia's efforts to introduce enrichment are also likely to face considerable legal, procedural, and political difficulties even after the conclusion of the 123 Agreement.

The U.S.-Saudi agreement would raise concerns from the perspective of nuclear nonproliferation. When the United Arab Emirates concluded a 123 Agreement with the United States in 2009, it renounced domestic enrichment and reprocessing and accepted the IAEA Additional Protocol. These arrangements became known as the "gold standard" of U.S. nuclear cooperation. Saudi Arabia, by contrast, has not permanently renounced enrichment and reprocessing and has not adopted the Additional Protocol. Crown Prince Mohammed bin Salman has even publicly stated that Saudi Arabia would develop nuclear weapons if Iran did so. The decision to open a pathway to Saudi enrichment is therefore likely to generate international controversy.

The U.S. Department of Energy has reportedly exempted Saudi Arabia from the requirement to adopt the Additional Protocol, which the United States has strongly demanded as a condition for nuclear cooperation. Washington instead argues that a separate U.S.-Saudi Bilateral Safeguards Agreement will enable a high level of verification and control. However, the contents of that agreement have not been disclosed, and it remains uncertain whether it will be more effective than the IAEA's enhanced safeguards measures.

The two confidential side letters are also important. According to media reports, one may contain provisions granting exclusive commercial rights to U.S. companies and restricting cooperation with third countries such as China and Russia. The other may include sensitive nuclear control conditions governing the ownership and operation of enrichment facilities, U.S. technological controls and monitoring, restrictions on the access of Saudi personnel, and the suspension of facility operations in the event of a violation.

It is therefore an exaggeration to describe the agreement as granting Saudi Arabia unrestricted permission to enrich uranium. Nevertheless, the fact that Saudi Arabia has been given a pathway toward acquiring enrichment facilities without the Additional Protocol requirement clearly represents a retreat from the traditional nuclear nonproliferation principles of the United States.

| Why Saudi Arabia Received an Exceptional Treatment on Uranium Enrichment and Nuclear Nonproliferation

Saudi Arabia has long been regarded as a country presenting significant nuclear proliferation risks. Nevertheless, the United States has now granted it exceptional treatment with respect to uranium enrichment and nuclear nonproliferation. The principal reason is that Washington places a high strategic value on Saudi Arabia in the Middle East.

The scenario that the United States is most determined to avoid is one in which Saudi Arabia becomes integrated into the nuclear power and nuclear fuel cycle systems of China or Russia, thereby falling within their geopolitical sphere of influence. Under such circumstances, Saudi Arabia could acquire Russian or Chinese enrichment technology and operate uranium enrichment facilities under nuclear nonproliferation and security standards less stringent than those required by the U.S. In fact, Saudi Arabia utilized the prospect of nuclear cooperation with Russia or China as leverage during its negotiations with the United States. Such an outcome would not only deprive the United States of a major nuclear power market but also undermine its ability to monitor and influence Saudi Arabia's nuclear program. To avoid this worst-case scenario, the Trump administration appears to have chosen an approach under which enrichment facilities would be established in Saudi Arabia under direct U.S. involvement and oversight.

Throughout the negotiations, the United States sought Saudi Arabia's accession to the Abraham Accords and normalization of relations with Israel as the price for permitting uranium enrichment. However, neither the initial media reports nor the official government announcements mentioned such a provision. Shortly thereafter, President Trump stated that the U.S.-Saudi nuclear agreement was contingent upon Saudi Arabia joining the Abraham Accords, creating considerable uncertainty regarding the future of the agreement. Saudi Arabia has consistently maintained that recognition of a Palestinian state is a prerequisite for joining the Abraham Accords, and its position has not changed. Strictly speaking, accession to the Abraham Accords is legally separate from the nuclear cooperation agreement. From President Trump's perspective, however, permitting Saudi Arabia to pursue enrichment represented a major political and diplomatic concession, and he appears to have expected corresponding political and diplomatic returns. Consequently, this debate is likely to continue for some time.

Commercial considerations also played a central role. Saudi Arabia's nuclear power program extends far beyond the construction of several nuclear power plants. It represents a market that will continue for decades, encompassing fuel supply, components, maintenance, regulatory support, workforce development, nuclear security, and cyber security. This explains why the Trump administration has highlighted exports by U.S. companies, job creation, and supply chain reconstruction as key achievements of the agreement. Ultimately, the U.S.-Saudi 123 Agreement reflects the combined influence of U.S. nuclear cooperation policy, nuclear exports, and geopolitical competition with China and Russia.

Saudi Arabia's negotiating strategy also proved effective. Riyadh refused to abandon the enrichment option until the end of the negotiations and leveraged the possibility of importing nuclear power plants from China, Russia, South Korea, or France if Washington declined its request. Whereas the Biden administration sought to link nuclear cooperation to Saudi-Israeli normalization and progress on the Palestinian issue, the Trump administration largely separated these issues. At a time when U.S.-Saudi relations had been strained by the Iran war, Washington appears to have viewed the nuclear agreement as a long-term mechanism for reinforcing bilateral relations.

The agreement also illustrates the pragmatic and differentiated application of U.S. nuclear nonproliferation principles. Although Washington regards uranium enrichment and reprocessing as sensitive technologies, it has not applied identical standards to every country. Instead, exceptions have been made on the basis of alliance relationships, a country's regional and strategic importance, geopolitical competition with China and Russia, the commercial interests of U.S. companies, and Washington's ability to maintain technological control. Saudi Arabia successfully leveraged these considerations.

| Opportunities and Challenges for South Korea's Pursuit of Uranium Enrichment

The most important implication of the Saudi agreement for South Korea is that U.S. cooperation on uranium enrichment is no longer a taboo. When strategic value, commercial interests, technological control, and enhanced verification are combined, the United States has shown that enrichment can be permitted.

Compared with Saudi Arabia, South Korea possesses a far stronger record and significantly greater capabilities in nuclear power plant operation and exports, nuclear nonproliferation and security, nuclear safety regulation, export controls, and implementation of IAEA safeguards. South Korea has been a party to the Additional Protocol since 2004 and has faithfully implemented its obligations, earning international recognition as a model state in the peaceful use of nuclear energy and nuclear nonproliferation. Moreover, in the November 2025 U.S.-ROK Summit Joint Fact Sheet, the United States expressed its support for procedures leading to South Korea's peaceful civilian uranium enrichment and spent fuel reprocessing, consistent with the U.S.-ROK 123 Agreement and applicable U.S. law.

By drawing on its exemplary nonproliferation record, its advanced peaceful nuclear capabilities, the mutual benefits of U.S.-ROK nuclear cooperation, and the precedent set by the Saudi case, South Korea will be in a stronger position to negotiate with the U.S. for the ability to develop uranium enrichment capability.

South Korea's interest in uranium enrichment is driven not by aspirations for nuclear weapons or national prestige. Although South Korea is one of the world's leading nuclear power operators and exporters, it remains entirely dependent on foreign suppliers for uranium enrichment services. The need to reduce dependence on Russian enrichment services and to respond to supply chain fragmentation and expanding global demand for nuclear power, and growing demand for advanced reactor fuels have all made nuclear fuel supply a serious energy security issue. Failure to secure enrichment services and various types of nuclear fuel in a timely manner could undermine both the continued operation of South Korea's nuclear power plants and the international competitiveness of its nuclear exports.

At the same time, the Saudi agreement may not necessarily work to South Korea's advantage. If it provokes strong opposition from the U.S. Congress and the nonproliferation community, Washington may impose even stricter conditions on any subsequent requests for enrichment in order to prevent the Saudi case from becoming a broader precedent. South Koreans should therefore be cautious about relying on an argument that simply asserts, "If Saudi Arabia is allowed, South Korea should be allowed as well," since such reasoning may have only limited persuasive value.

In fact, under the Saudi agreement, any enrichment program would be conditioned upon a joint feasibility assessment with the United States, a ten-year prohibition on pursuing enrichment if the assessment reaches a negative conclusion, a prohibition on developing indigenous enrichment technology, the exclusive use of U.S.-supplied enrichment facilities, and U.S. bilateral oversight and technological control of the facilities. It remains questionable whether accepting these conditions in their entirety would be consistent with the long-term interests of South Korea's expanding civilian nuclear energy program, its technological independence, and its broader nuclear fuel cycle objectives.

Saudi Arabia also differs from South Korea in important respects. Although Riyadh maintains an alliance relationship with the United States, it has traditionally pursued a strategy of hedging by maintaining relations with multiple great powers. The United States needs Saudi Arabia as a central pillar of its Middle East strategy, while Saudi Arabia depends heavily on U.S. security guarantees. Under the current regional security environment, Riyadh has a strong interest in ensuring that the United States does not substantially reduce its military presence in the Middle East, while continuing to rely on U.S. security commitments to deter Iranian military threats. The exchange of these mutual strategic interests was a principal factor underlying the outcome of the nuclear negotiations.

| Implications for South Korea's Nuclear Diplomacy with the United States

South Korea must first clearly articulate, at the national level, why it needs uranium enrichment. It should officially and consistently emphasize, both domestically and internationally, that the objective of enrichment is not to acquire a latent nuclear weapons capability or enhance national prestige, but rather to support the sustainable use of nuclear energy, ensure the stability of the nuclear fuel supply, facilitate nuclear power exports, and secure fuel for next-generation reactors as part of a peaceful civilian nuclear energy policy. If domestic discussions continue to conflate uranium enrichment with nuclear armament or latent nuclear capability, it will become far more difficult to obtain U.S. consent, and South Korea's pursuit of enrichment itself may increasingly be perceived as a proliferation risk.

Maintaining a close and stable relationship with the United States is an essential prerequisite and a valuable diplomatic asset. Unlike Saudi Arabia, South Korea is not a country that engages in hedging diplomacy between the United States and China or between the United States and Russia in order to extract a better deal from Washington. South Korea is a U.S. ally, a model member of the international nuclear nonproliferation regime, and a country that operates within the institutional framework of U.S.-ROK nuclear cooperation. These critical differences suggest that, rather than attempting to replicate Saudi Arabia's diplomatic and negotiating approach, South Korea should pursue enrichment negotiations by maintaining a stable alliance with the United States and its credibility in nuclear nonproliferation while building upon shared interests, including nuclear fuel supply chain security, the commercial interests of the U.S. nuclear industry, joint technological development, and cooperation in international nuclear markets.

For South Korea, nuclear nonproliferation should be regarded not as an obstacle to uranium enrichment but as its most valuable diplomatic asset. South Korea could limit enrichment exclusively to the production of commercial low-enriched uranium (LEU), while proactively proposing ceilings on enrichment levels and production volumes, restrictions on stockpiles of nuclear material, phased expansion based on actual fuel demand, and transparency and verification measures as required by the IAEA Additional Protocol. At the same time, South Korea should give priority to developing indigenous enrichment technology to strengthen its energy security, while also considering, where appropriate, equity investment in U.S. enrichment facilities and the introduction of black-box enrichment facilities for mutual benefit of the two countries.

Above all, the government should manage the enrichment issue consistently as a long-term national agenda rather than as a short-term political slogan. The Office of the President and the National Security Office should provide overall leadership, while the Ministry of Foreign Affairs and the ministries responsible for nuclear energy, energy policy, industry, and science and technology should jointly develop a unified policy and negotiating strategy. Particular caution is required because if discussions of South Korea's enrichment and reprocessing policy become intertwined with issues such as acquiring a latent nuclear weapons capability or domestically enriching fuel for nuclear-powered submarines, the United States is likely to delay cooperation on uranium enrichment.

In conclusion, if South Korea seeks to acquire uranium enrichment and spent fuel reprocessing capabilities, it must first establish the necessary domestic foundation. To that end, it should consider enacting a "Basic Law on the Peaceful Use of Nuclear Energy" to codify the principles governing the peaceful use of nuclear energy and the responsibilities of the government. It should also consider adopting a "Basic Law on Nonproliferation" that explicitly renounces nuclear weapons development while strengthening the domestic implementation of international nonproliferation obligations. In addition, a U.S.-ROK Nonproliferation and Nuclear Cooperation Fund should be established to support joint research, verification technologies, nuclear fuel supply chains, and the development of fuels for next-generation reactors.

There is an American saying: "If I had six hours to chop down a tree, I would spend four sharpening the axe." Likewise, strengthening the relevant legal and institutional framework constitutes essential preparation for introducing uranium enrichment and spent fuel reprocessing, while also providing the foundation for successful negotiations. Such measures are not merely diplomatic or institutional formalities; they represent a serious declaration, both domestically and internationally, that South Korea possesses both the capability and the commitment to pursue the peaceful use of nuclear energy while upholding nuclear nonproliferation. This institutional foundation will serve as the basis for advancing the introduction of uranium enrichment and spent fuel reprocessing.

※ The opinions expressed in 'Sejong Focus' are those of the author and do not represent the official views of Sejong Institute.