[Global NK Commentary] The Three-Stage Denuclearization Theory and the END Framework: Issues and Limitations of the South Korean Government's Denuclearization Approach

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Introduction[1]

This article examines the impact of the conceptual ambiguity of the denuclearization phased approach and the 'END (Exchange–Normalization–Denuclearization) Framework,' raised in the context of South Korea-U.S. North Korea policy in the second half of 2025, on policy consistency and deterrence credibility. Despite eight months having passed since the Trump administration's inauguration and four months since the Lee Jae-myung administration's inauguration, the absence of official North Korea and denuclearization strategy documents from both countries means that presidential remarks, interviews, and domestic and international speeches are substituting for policy. Concurrently, North Korea, at the December 2023 plenary meeting of the Workers' Party of Korea, shifted its relations with South Korea to 'hostile inter-state relations,' and through the Supreme People's Assembly in January 2024, Kim Yo-jong's statements in 2025, and Kim Jong-un's speeches, has repeatedly confirmed a line that negates the very premise of dialogue. Amidst these structural changes, a re-examination is needed to determine whether declarative phase distinctions such as 'interruption–reduction–dismantlement' can drive actual deterrence and negotiation dynamics.

This paper addresses three core questions. First, it assesses the implications of the terminological and conceptual differences between the 'freeze–reduction–dismantlement' and 'interruption–disarmament–complete denuclearization' presented by the South Korean government for policy choices and mutual verification systems. Second, it examines how the institutionalization of multi-layered missile defense and extended deterrence by the United States (NCG) and the strengthening of homeland defense symbolized by Executive Order 14186 ('The Iron Dome for America,' also known as 'Golden Dome') are asymmetrically intertwined with South Korea's security dilemma, particularly the direct threat from tactical nuclear forces such as the KN-23. Finally, it investigates the risk that an approach linking 'interruption (stop)' with compensation, in a situation where signs of operationalization of tactical systems tested on the Ukrainian battlefield by North Korea are confirmed, could lead to the solidification of de facto nuclear-weapon state status and a verification vacuum.

To this end, we utilize statements by the South Korean President, speeches at the UN General Assembly, interviews, and materials from the Presidential Office. We also refer to U.S. executive orders, public defense-related materials, and Congressional Research Service (CRS) reports. Official documents and primary reports from North Korea's Supreme People's Assembly, Workers' Party documents, and Korean Central News Agency statements were compared and analyzed.

Threat Environment and Policy Context

The current situation is assessed as one where individual remarks and fragmented principles are being presented without clear articulation, rather than a clear principle from the South Korean government and a coordinated strategy between South Korea and the U.S. Firstly, the South Korean government's perception of North Korea's nuclear threat appears to be focused on threats to the U.S. homeland rather than those imposed on South Korea. President Lee Jae-myung, in his remarks at the New York Stock Exchange on September 25 (local time), introduced his summit with President Trump on August 25.[2] President Lee stated that he emphasized three points. First, that North Korea has nearly completed the development of intercontinental ballistic missiles (ICBMs), nuclear weapons capable of striking the U.S. homeland. This conveys the message that the U.S. must engage in dialogue with North Korea immediately, as its homeland is under threat. Second, he presented the possibility of North Korea continuing to produce approximately 15 to 20 nuclear bombs annually and exporting them. This is also a warning that if North Korea is not deterred, there is a risk of nuclear proliferation to terrorist groups, which the U.S. considers extremely sensitive. Third, he argued that therefore, merely stopping North Korea's ICBM and nuclear production capabilities would yield "significant security benefits." The implication is that only Trump has the capability and will to stop North Korea, and thus negotiations should commence quickly. Notably absent from this discussion is North Korea's existential nuclear threat to South Korea, which is profound. Only North Korea's nuclear attack capability against the U.S. homeland, which remains uncertain, was emphasized. While President Lee's emphasis can be understood as an attempt to persuade Trump to engage in U.S.-North Korea dialogue, it is insufficient. Even if North Korea's capability to strike the U.S. is in the final stages of development, the U.S. still has a buffer.

The current Trump administration is fully engaged in countering China's nuclear buildup and aggressive nuclear strategy. Immediately after taking office, on January 27, President Trump signed Executive Order 14186, "The Iron Dome for America," later renamed "Golden Dome" by Trump.[3] The order outlines three policy directions: (1) deployment and maintenance of next-generation missile defense systems, (2) deterrence and defense against all foreign homeland aerial attacks, and (3) ensuring secure second-strike capabilities. To achieve this, the U.S. is strengthening its defenses against ballistic, hypersonic, and advanced cruise missiles, as well as next-generation aerial attacks. Specifically, it is accelerating the deployment of space-based sensor layers for tracking hypersonic and ballistic missiles and developing and deploying space-based interceptors capable of intercepting missiles in their boost phase. Furthermore, it is enhancing terminal-phase intercept capabilities to prevent attacks on high-value targets (e.g., cities) by adversaries and expanding capabilities to neutralize missile attacks in the boost and pre-boost phases. While controversial in terms of feasibility, it is a fact that the U.S. is building a 'multi-layered defense network' to intercept missiles at various stages, including space, ground, and early launch. Therefore, it is reasonable to assume that the U.S.'s advanced defense capabilities, enhanced to counter China, are sufficient to address North Korea's ICBMs, whose completion is still uncertain. During his confirmation hearing on September 24, the nominee for Chairman of the South Korean Joint Chiefs of Staff testified that North Korea's ICBM re-entry capability appears to be unverified.[4]

Unlike the U.S., which can be considered virtually secure due to its superior defensive and formidable offensive capabilities, South Korea is severely exposed to North Korean threats. In May 2019, while U.S.-North Korea negotiations were actively underway and the South Korean Moon Jae-in administration was promoting the Korean Peninsula Peace Process, North Korea test-fired for the first time a missile equipped with a low-yield nuclear warhead, the KN-23, with a range of 690 km capable of striking all of South Korea. Subsequent development has continued, and according to a May 2025 U.S. Congressional Research Service report, North Korea has sufficiently tested this missile on the Russia-Ukraine battlefield and confirmed its operational readiness to attack South Korea.[5]

Therefore, during his meeting with Trump, the South Korean President should have emphasized the existential threat of North Korean nuclear weapons to South Korea rather than the threat to the U.S. homeland, and reaffirmed the U.S. extended deterrence commitment. He should have requested that the institutionalization of extended deterrence through the 'Nuclear Consultative Group' (NCG), initiated by the previous Biden administration, proceed as originally planned, and specifically sought security assurances for the Korean Peninsula. The Biden administration had repeatedly stated, through presidential remarks and official government documents, its commitment that any North Korean nuclear use would result in the end of the regime.

Denuclearization Phased Approach and North Korea's Position

The three-stage denuclearization approach presented by the South Korean government also requires more detailed explanation of its principles. The terminology used has changed several times. Initially, it was freeze, reduction, and dismantlement, but[6] in President Lee's interview with TIME magazine, it was interruption (stop), disarmament, and complete denuclearization,[7] and the expression used in his UN speech on September 23 (local time) was stop, reduction, and dismantlement.[8] According to Presidential Office National Security Advisor Wi Sung-lac, it was initially referred to as freeze, but "interruption is a more accurate term," so it was adopted.

However, agreements previously concluded with North Korea, such as the 1994 Agreed Framework, used the term freeze. In the context of denuclearization, the concept used is freeze, not interruption. Freeze is a formal procedure that specifies the object and verifies compliance, whereas interruption is an ambiguous concept. It is unclear whether it means merely stopping production, halting facility operations, or simply stating that nuclear and missile development will not proceed. This conceptual difference is clearly demonstrated by the frequent use of the phrase "freeze and verify" in non-proliferation and denuclearization documents and analytical papers. For example, a report by the United Nations Institute for Disarmament Research (UNIDIR) explains that freeze includes the suspension of all nuclear material production activities, aiming to minimize the possibility of concealment or diversion and enhance traceability.[9] Unlike a mere declarative halt, freeze encompasses measures to stop the production, processing, and reprocessing of nuclear materials, and securing verifiability while that state is maintained is key. However, President Lee stated in his TIME magazine interview that compensation could be provided to North Korea if it halts its activities.[10] Without a specific definition of interruption, it can be interpreted as emphasizing compensation, which ultimately means the lifting of sanctions against North Korea. If such a situation unfolds, North Korea would effectively become a nuclear-weapon state early in the denuclearization negotiations, and based on past experience, progress would be nearly impossible thereafter. Negotiations with North Korea have always broken down due to North Korea's failure to properly comply with verification.

Furthermore, as mentioned earlier, Kim Jong-un, General Secretary of the Workers' Party of Korea, clearly stated in his speech at the Supreme People's Assembly, over approximately 40 minutes, "the current state and compatibility of relations with the U.S. and South Korea, and the principled stance to be maintained in external activities."[11] He clearly expressed his rejection of the South Korean government's proposed three-stage denuclearization theory, calling it a "copy of the homework assignment" from previous administrations who dreamed of our disarmament, referring to the current administration's so-called "interruption–reduction–denuclearization" "three-stage denuclearization theory."

The North Korea policy framework presented by the current administration also requires explanation. The END framework, derived from the first letters of Exchange, Normalization, and Denuclearization, appears to have a priority and sequence, despite National Security Advisor Wi Sung-lac's denial. It is common sense that normalization of relations can only occur after exchanges. Denuclearization is positioned thereafter. Moreover, Advisor Wi is reported to have explained the END framework as a "principle emphasized in the 2018 U.S.-North Korea Singapore Joint Statement, etc.," which further implies a priority. The Singapore agreement's core contents are (1) establishment of new U.S.-North Korea relations, (2) a durable peace regime on the Korean Peninsula, and (3) denuclearization of the Korean Peninsula. Following the agreement, when then-Secretary of State Michael Pompeo visited North Korea to demand denuclearization, North Korea issued a statement through its Foreign Ministry spokesperson on July 7, criticizing that the Singapore agreement had a sequence, and that "only the coercive demand for denuclearization was brought up, contrary to the spirit of the talks."[12] Regardless of South Korea's denial, North Korea insists on a sequence. If South Korea desires improved relations with North Korea, denuclearization must be de-emphasized or omitted entirely for North Korea to even consider engagement. In this scenario, the reduced emphasis on denuclearization could further endanger South Korea's security.

Policy Recommendations and Conclusion

A more realistic assessment is that North Korea is highly unlikely to engage with South Korea for the foreseeable future. Kim Jong-un's speech at the Supreme People's Assembly and Kim Yo-jong's statements confirm this. North Korea, at the 8th Party Congress, 9th Plenary Meeting in December 2023, already finalized its policy of declaring relations with South Korea as 'hostile inter-state relations.'[13] Regardless of the nature of the North Korean regime, a change in state strategy requires formal procedures. However, North Korea emphasizes its lack of intention to change its policy. Kim Jong-un stated, "We have no reason to sit down with South Korea and will do nothing with them. We will make it clear that we will not engage with them in any way." He further asserted towards the South Korean government, "The reality is that regardless of whether they claim to be 'democratic' or wear the guise of 'conservative,' South Korea's inherent ambition to collapse our system and regime has never changed and never will, and they are clearly showing that the enemy is the enemy." A speech with precisely the same wording was delivered at the Supreme People's Assembly in January 2024,[14] and Kim Yo-jong also issued a similar statement.[15] Regardless of the South Korean government's political leaning, the message is 'we will not associate with you.'

However, North Korea implies that it may establish relations as individual states if South Korea takes the following measures. First, it demands the cessation of all types of joint military exercises. Since the inauguration of the Trump administration, North Korea has consistently criticized and condemned all exercises involving South Korea and the U.S. Kim Jong-un's and Kim Yo-jong's speeches and statements also interpret joint exercises as "war frenzies" and ultimately demand their permanent cessation.[16]

Second, it demands that South Korea amend its constitution to remove provisions hostile to North Korea. Kim Jong-un's speech invokes the era of President Syngman Rhee and criticizes that "by embedding the phrase 'The territory of the Republic of Korea shall be the Korean Peninsula and its adjacent islands' in the first Constitution of the Republic of Korea, fabricated and promulgated in July 1948, the inherently hostile nature towards our state was codified."[17] Although North Korea has stated its intention to include similar provisions in its constitution, the status of the South Korean constitution is incomparably higher than that of the North Korean constitution. Therefore, it can be interpreted as a demand for South Korea to ultimately accept North Korea's 'hostile inter-state theory' by amending its constitution. For reference, the North Korean constitution is subordinate to the Workers' Party rules, which are in turn subordinate to the leader's directives.

Finally, it demands the withdrawal of U.S. Forces Korea and the dissolution of the alliance. Kim Jong-un stated, "Reunification is absolutely unnecessary," and defined South Korea as a country that "entrusts its politics and defense to foreign powers."[18] This is a message that if South Korea desires a deep relationship with North Korea, including discussions on reunification, it must break ties with the United States. North Korea also knows that it is impossible for South Korea to accept all three conditions, and therefore, it can be interpreted as an attempt to thoroughly exclude South Korea under this pretext.

What the South Korean government must do now is first to formally establish and explain its principles accurately. As it has been in office for less than four months, it may take more time to formalize its core policies. In that case, rather than revealing principles and concepts piecemeal, it should promptly formulate and explain to the public and announce to the international community a unified policy on North Korea, unification, and denuclearization to prevent confusion.

Above all, cooperation with the United States is crucial. Although the Trump administration has been in office for eight months, it has not yet announced its official North Korea policy. Despite the North Korean nuclear issue being an existential threat that takes precedence for South Korea, the U.S. is the primary actor in denuclearization negotiations. Therefore, South Korea must urgently consult closely with the U.S. to align its North Korea and denuclearization policies. If the U.S. disagrees with the three-stage approach advocated by South Korea, South Korea's credibility will diminish. Since North Korea thoroughly excludes South Korea, it is imperative to reflect South Korea's position through the U.S. and create space for improving inter-Korean relations. The South Korea-U.S. relationship has thus become even more important.

Specifically, the terminology of the three-stage denuclearization theory, which has been used interchangeably, needs to be redefined from the perspective of verifiability, binding force, and linkage to compensation to minimize errors in policy translation. The asymmetry in threat perception between 'homeland-centric deterrence' and 'threats facing South Korea' must be revealed, and practical guidelines for extended deterrence that bridge this gap, such as clarifying redlines, maintaining visible combined forces posture, and establishing rapid consultation procedures during crises, must be further developed. Even with North Korea's entrenched non-cooperative stance towards South Korea, negotiations should be presented as a means and deterrence as the goal, with 'freeze and verify' as the initial phase standard, thereby enhancing the consistency of the South Korea-U.S. cooperation framework and messages to North Korea.

In conclusion, this paper has demonstrated that while the South Korean government's 'Three-Stage Denuclearization Theory' and 'END Framework' possess a declarative structure, they require structural improvements in conceptual clarity (contrasting 'interruption' with 'freeze and verify'), focus of threat perception (homeland-centric versus threats facing South Korea), and implementation mechanisms (institutionalization and visualization of extended deterrence). As North Korea defines inter-Korean relations as 'hostile inter-state relations' and undermines the premise of negotiations, the operationalization of tactical systems on the Ukrainian battlefield and short- and medium-range threats such as the KN-23 directly impact South Korea's security. Therefore, South Korea must standardize its policy terminology to 'freeze & verify' and further institutionalize operational guidelines for extended deterrence between South Korea and the U.S., including the documentation of redlines, constant visualization of combined forces, and rapid consultation procedures during crises. Messages to North Korea should be based on the principle that negotiations are a means and deterrence is the goal, with the phased design reconfigured, and compensation should be allowed only restrictively, linked to verification and safeguards against reversal. Only when conceptual consistency and alliance effectiveness are combined can the rhetoric of 'END' be transformed into a strategy that reduces actual risks. ■

[1]This paper is an expanded and deepened version of the author's "Beyond the Eucharist of Words, North Korea's Nuclear Weapons and the Reality of South Korean Security" (JoongAng Ilbo Perspective, September 20, 2025).

[2]Republic of Korea Government, "Press Release: President Lee Emphasizes Efforts to Resolve 'Geopolitical Risks' During Visit to New York Stock Exchange," September 25, 2025.

[3]Executive Order 14186, "The Iron Dome for America," Federal Register 90 FR 8767 (February 3, 2025), signed January 27, 2025.

[4]Request for Personnel Hearing for the Chairman of the Joint Chiefs of Staff Nominee (Jin Young-seung) (President), National Assembly Bill Information System (Material Submitted to the National Defense Committee).

[5]Congressional Research Service, "North Korea's Nuclear Weapons and Missile Programs," May 23, 2025, https://www.congress.gov/crs_external_products/IF/PDF/IF10472/IF10472.39.pdf

[6]Office of the President of the Republic of Korea, "President Lee Jae-myung's Interview with Yomiuri Shimbun," August 19, 2025.

[7]Time Magazine, "President Lee Jae-Myung's Plan to Reboot South Korea," September 17, 2025, https://time.com/7317953/south-korea-president-lee-jae-myung-cover/

[8]Korea Times, "S. Korean President Lee Jae Myung's UN General Assembly Address," September 23, 2025, https://www.koreatimes.co.kr/foreignaffairs/20250924/full-text-s-korean-president-lee-jae-myungs-un-general-assembly-address.

[9]Pavel Podvig, "Freeze and Verify: Ending Fissile Material Production on the Korean Peninsula," United Nations Institute for Disarmament Research (UNIDIR), Geneva, Switzerland, 2020, p. 9, https://unidir.org/wp-content/uploads/2023/05/FreezeandVerify.pdf.

[10]The original English text is as follows: “As our short-term goal, we should stop their nuclear and missile programs. And we might be able to compensate them for some of these measures and afterwards then pursue disarmament and then complete denuclearization.”

[11]"Report on the 13th Session of the 14th Supreme People's Assembly of the Democratic People's Republic of Korea," Rodong Sinmun, September 22, 2025.

[12]DPRK Ministry of Foreign Affairs Spokesperson, "Statement on the Position After High-Level DPRK-U.S. Talks," Korean Central News Agency, July 7, 2018.

[13]Korean Central News Agency, "Report on the 9th Plenary Meeting of the 8th Central Committee of the Workers' Party of Korea," December 30, 2023.

[14]Korean Central News Agency, "Report on the 10th Session of the 14th Supreme People's Assembly," January 16, 2024.

[15]Kim Yo Jong, Vice Department Director of the Central Committee of the Workers' Party of Korea, Statement, "The Relationship Between North and South Korea Has Completely Exceeded the Timeframe of the Concept of Compatriots," Korean Central News Agency, July 28, 2025.

[16]"Report on the 13th Session of the 14th Supreme People's Assembly of the Democratic People's Republic of Korea," Rodong Sinmun, September 22, 2025.

[17]"Report on the 13th Session of the 14th Supreme People's Assembly of the Democratic People's Republic of Korea," Rodong Sinmun, September 22, 2025.

[18]"Report on the 13th Session of the 14th Supreme People's Assembly of the Democratic People's Republic of Korea," Rodong Sinmun, September 22, 2025.

■ Park Won Gon_Director of the EAI North Korea Research Center; Professor of North Korean Studies at Ewha Womans University.

■ Responsible for and Edited by: Lee Sang Jun_EAI Researcher

    Inquiries: 02 2277 1683 (ext. 211) | leesj@eai.or.kr