“Snapback” Mechanism: A Final Deterrent or Gateway to Escalation with Iran?

Prepared by/ Dina Ehab

Research Assistant in the Middle East Affairs Unit

Amid escalating regional and international tensions surrounding Iran’s nuclear file, the “snapback” mechanism—formally known as the automatic reimposition of UN sanctions—has re-emerged at the forefront of political and diplomatic discourse, following mounting European threats against Tehran. On Tuesday, July 15, 2025, French Foreign Minister “Jean-Noël Barrot” declared that France would not hesitate to activate this mechanism should efforts to reach an agreement on Iran’s nuclear program fail, affirming that the E3—France, Germany, and the United Kingdom—retain the right to reimpose sanctions on arms, the banking system, and nuclear equipment that had been lifted ten years ago.[1] This statement coincided with the German Chancellor’s announcement of his country’s intention to formally submit a request to the UN Security Council to trigger the same mechanism, in a clear indication of Europe’s increasingly hardline position in response to the stalled negotiations with Iran. In turn, Tehran categorically rejected these threats, describing any potential activation of the snapback mechanism as an unjustified escalation that lacks legal and moral grounds and reflects, in its view, a hostile political posture by the European states. Iran also asserted that it would respond to any such move accordingly, [2]signaling the beginning of a new phase of mutual escalation and raising fundamental questions about the legal validity, the limits of effectiveness of this mechanism in confronting Iran, and the possibility of containing the crisis within current diplomatic frameworks.

Firstly: The Framework of the “Snapback” Mechanism

The “Snapback” mechanism is considered one of the most prominent legal tools in the Iranian nuclear dossier, as it combines procedural power with high-stakes political impact, as outlined below:

1- Origins under the Obama Administration:

The roots of the Snapback mechanism date back to former U.S. President Barack Obama’s administration, which negotiated the Joint Comprehensive Plan of Action (JCPOA) with Iran in 2015 in coordination with the five permanent members of the UN Security Council, along with Germany, within the multilateral framework known as the P5+1. The U.S. administration at the time insisted on embedding the Snapback clause within UN Security Council Resolution 2231 as a means of safeguarding the agreement from any future obstruction, [3] particularly by Russia or China. The mechanism was designed to ensure the implementation of the deal’s provisions through an implicit threat of the swift reimposition of UN sanctions in case of Iranian non-compliance. However, this legal instrument—which remained unused during Obama’s tenure due to Iran’s relative compliance—functioned more as a diplomatic safety net than a tool for direct confrontation.

2- The Procedural Function of the “Snapback” Mechanism:

The Snapback mechanism possesses a unique procedural sensitivity that renders it one of the most potent legal instruments within the UN system. If any party to the nuclear agreement submits a formal complaint to the Security Council claiming a “significant breach” by Iran, the Council is granted a 30-day window to vote on a draft resolution that would uphold the suspension of sanctions. [4] The critical paradox of this mechanism lies in the fact that the complaining state can veto this resolution, thereby automatically triggering the reinstatement of all previous UN sanctions without requiring any further vote. In this sense, the mechanism entails an almost automatic reactivation of the sanction’s regime, contingent on the political will of a single party. The steps required to activate the mechanism are as follows:

• The party that believes Iran is in non-compliance submits a written complaint to the “Joint Commission,” composed of representatives from all signatory states to the agreement.

• The Commission is given a 15-day period to resolve the dispute through negotiations.

• If the issue remains unresolved, the matter is escalated to the foreign ministers of the participating countries, who are granted an additional 15 days for discussion.

• During this period, the complaining party may—though it is not obligated to—request an opinion from a three-member advisory panel of experts, which must deliver its findings within 15 days.

• If all these steps fail to yield a resolution, the complaining party may refer the case to the UN Security Council.

• A draft resolution is then submitted to the Council affirming the continued lifting of sanctions on Iran.

• If the Security Council fails to adopt the resolution within 30 days, all international sanctions previously imposed on Iran are automatically reinstated.

3- The Limits of Veto Power in the “Snapback” Mechanism:

One of the most distinctive features of the Snapback mechanism is that it theoretically and practically restricts the use of the veto by Iran’s traditional allies, such as Russia or China. Since UN Security Council Resolution 2231 had already endorsed the condition of the automatic reimposition of sanctions, the vote within the Council is not on whether to impose sanctions, but rather on whether to continue lifting them. Therefore, the aggrieved party (such as France or the United Kingdom) can block the draft resolution to extend the sanctions relief by exercising its veto, which in turn automatically leads to the reactivation of the previous sanctions. As a result, other members of the Security Council, including Iran’s allies, have no effective means to prevent this outcome. In this context, the veto power is transformed from an instrument of obstruction into a tool of enforcement in the hands of the complaining party—an unprecedented shift in the legal architecture of international resolutions. Nevertheless, the mechanism remains the subject of considerable legal and political controversy, as it overrides the principle of collective consensus that is presumed to underpin the decision-making process within the Security Council.

4- Renewed Discourse on Activation of the Mechanism:

On July 14, 2025, coinciding with the tenth anniversary of the signing of the nuclear agreement between Iran and the P5+1 group, European threats to reactivate the Snapback mechanism resurfaced. This came in response to Iran’s shift in its stance toward cooperation with the International Atomic Energy Agency (IAEA) and Tehran’s threats to withdraw from the Treaty on the Non-Proliferation of Nuclear Weapons (NPT), following attacks on its nuclear facilities in the aftermath of the Twelve-Day War in June 2025.[5] following attacks on its nuclear facilities in the aftermath of the Twelve-Day War in June 2025.

Secondly: Messages Behind the Timing

The renewed and forceful discourse surrounding the potential activation of the Snapback mechanism against Iran—should nuclear talks fail to yield tangible results—reflects a notable shift. With Paris, Berlin, and London aligning on the matter, it has become evident that Europe has chosen to move beyond its previous hesitations and join Washington in a coordinated escalation against Tehran. However, what is particularly striking about the timing of this escalation is that it does not merely represent a technical response to stalled negotiations, but rather a deliberate and multi-layered strategic move, as outlined below:

1- Renewed Alignment Between Washington and Europe Following the NATO Summit:

Reflecting on the previous U.S. attempt to trigger the Snapback mechanism in 2020, Washington failed to secure the backing of its European allies in the Security Council when it unilaterally sought to reimpose the arms embargo on Iran, especially after the Trump administration’s 2018 withdrawal from the nuclear deal without coordinating with its European partners.[6] Today, however, following the NATO summit on June 24, 2025, strong signals have emerged indicating a recalibration in U.S.-European relations. This realignment has repositioned Europe within the broader “maximum pressure” strategy against Iran. Recognizing the limitations of unilateral action, the United States has pushed for deeper European involvement, resulting in a unified and coordinated stance aimed at amplifying pressure on Iran’s nuclear program.

2- Unified Position in Exchange for Trade Concessions:

Europe’s policy shift cannot be explained solely by a change in political sentiment; it may also reflect the possibility of an unannounced economic quid pro quo between Europe and the United States. The European capitals’ entry into the pressure campaign against Iran, alongside Washington, has coincided with progress in U.S.-EU negotiations over easing protectionist trade measures and tariffs that were reinstated following Trump’s return to the White House. In this context, it is plausible that Washington encouraged Europe to adopt a more assertive posture on the Iran file in exchange for tariff reductions on European goods and expanded access to U.S. markets for certain sectors.

3- The Critical Timing Factor:

Adding to the above is a decisive temporal consideration: Russia is set to assume the rotating presidency of the UN Security Council at the end of 2025. Given that Moscow is one of Tehran’s most prominent allies, any future attempt to trigger the Snapback mechanism under its presidency would likely encounter significant political and procedural obstacles. Thus, European states appear to be accelerating efforts to activate the mechanism before Russia gains the ability to obstruct—or at least constrain—any Western initiative against Iran under the Security Council’s framework.

Thirdly: Potential Implications of Triggering the Snapback Mechanism

Activating the Snapback mechanism represents a legally and politically significant step, as it entails the reimposition of all international sanctions that were lifted under UN Security Council Resolution 2231, which endorsed the Iran nuclear agreement. Under this mechanism, these sanctions would be automatically reinstated within a short period not exceeding thirty days. Legally, such action would nullify the practical effectiveness of the nuclear deal, which had constituted an international framework for managing Iran’s nuclear program, and would substantially reinforce the trajectory of confrontation rather than dialogue and negotiation.

Politically, triggering the mechanism would create a deadlock in relations between Iran and the West, prompting the Iranian regime to adopt more hardline positions. This could result in a complete withdrawal from the nuclear agreement or even from the Treaty on the Non-Proliferation of Nuclear Weapons (NPT). It may also lead to heightened tensions across the Gulf and the broader Middle East through increased Iranian military activity and expanded support for its regional proxies—posing a threat to regional stability and prompting neighbouring states to adopt more cautious or escalatory policies in response.

Economically, the reimposition of international sanctions would further intensify Iran’s financial isolation, particularly through targeting its banking sector and severing its links to global markets. This would exacerbate the pressure on the already strained Iranian economy, which continues to suffer from high inflation rates and declining growth. On the security and strategic front, Iran is expected to respond to the sanctions escalation by deepening its nuclear and missile programs. This may include raising uranium enrichment levels to near-weapons-grade thresholds, thereby increasing the likelihood of international crises concerning the risks of nuclear proliferation, and potentially escalating confrontations with key regional and international actors—especially the United States and Israel.

At the international level, the activation of the Snapback mechanism is likely to result in a sharp division within the UN Security Council. Russia and China are expected to oppose the move, viewing it as an undermining of the international agreement and a threat to the political consensus that underpinned Resolution 2231. Such division would weaken the Council’s ability to act collectively, deepen tensions among major powers, and damage the credibility of the collective security system—making the prospects for future diplomatic solutions far more difficult.

Fourthly: Iran’s Position in Response to the Mechanism

Iran has officially objected to the European threats of activating the Snapback mechanism, considering such a move to lack legal and political justification. From Tehran’s perspective, it constitutes an escalatory step that does not serve the path toward resolving the nuclear agreement. This position was expressed through statements by the spokesperson for Iran’s Ministry of Foreign Affairs, who asserted that resorting to this mechanism does not align with current realities—especially given what he described as Iran’s continued commitment to the negotiation track, despite facing internal and external challenges.

Tehran also criticized the performance of the International Atomic Energy Agency (IAEA), accusing it of double standards and pointing to what it sees as a disregard for the issue of U.S. nuclear weapons stationed in Germany—a situation it claims contradicts Germany’s obligations as a party to the Treaty on the Non-Proliferation of Nuclear Weapons (NPT). Iran argued that the lack of accountability or action by the IAEA on this matter reinforces the perception of politicization in handling the Iranian nuclear file and undermines confidence in the impartiality of certain international institutions.[7]

In the same context, Iran reiterated its position that the three European countries—Germany, France, and the United Kingdom—have failed to uphold their commitments under the Joint Comprehensive Plan of Action (JCPOA), which prompted Iran to take reciprocal steps to reduce its own obligations, in accordance with the provisions of the agreement itself. Within this framework, Tehran holds these parties partially responsible for the current state of deadlock and calls for a comprehensive review of the implementation process by all stakeholders.

Finally, Iran stated that it is closely monitoring ongoing discussions on the Snapback mechanism in diplomatic forums and reserves the right to respond in a manner it deems appropriate should escalatory steps be taken without prior agreement or a clear legal consensus. It also affirmed the continuation of its consultations with European parties and emphasized its commitment to safeguarding its national interests within the broader framework of the nuclear deal, while urging against the politicization or instrumentalities of international legal mechanisms in ways that could threaten regional stability.

In Conclusion:

The Snapback mechanism emerges as an international legal tool with inherently contradictory dimensions. On one hand, it holds the potential to preserve the Iran nuclear agreement through legal deterrence; on the other hand, it represents a source of escalation and tension that threatens regional stability and complicates diplomatic negotiation processes. The current momentum toward activating this mechanism reflects strategic shifts and a relative convergence between the United States and Europe aimed at exerting joint pressure on Iran—making this file more complex than ever before. Conversely, Iran has firmly rejected this course of action, which underscores the urgent need to regulate the use of the mechanism within a framework of dialogue and mutual understanding, rather than confrontation, in order to safeguard the prospects for regional peace and security.

References:

[1] الترويكا الأوروبية تهدد بإعادة العقوبات الأممية على إيران نهاية أغسطس، صحيفة الشرق الأوسط، تاريخ النشر: ١٥ يوليو ٢٠٢٥، متاح على الرابط: https://share.google/ivhKTIJRAnCcOglkO

[2] “بشكل مناسب”.. إيران تلوح بالرد على إعادة تفعيل “آلية الزناد”، العربية، تاريخ النشر: ١٤ يوليو ٢٠٢٥، متاح على الرابط:

https://share.google/dItu82OUrNkLMyFxM

[3] ما هو قرار 2231 لمجلس الأمن الذي يعتبر مفتاحا للأزمة النووية الإيرانية؟ ميدل إيست نيوز، تاريخ النشر: ١٨ أبريل ٢٠٢١، متاح على الرابط:  https://share.google/iv4bW8Xtucr1mxugC

[4] آلية سناب باك، سكاي نيوز العربية، تاريخ النشر: ٢٠ أغسطس ٢٠٢٠، متاح على الرابط: https://share.google/d0d7URBktkbWEtyy9

[5] “آلية الزناد” ورقة ضغط تلوح بها أوروبا ضد البرنامج النووي الإيراني، الجزيرة نت، تاريخ النشر: ١٥ يوليو ٢٠٢٥، متاح على الرابط: https://linksshortcut.com/KYXyH

[6] مجلس الأمن يناقش الاتفاق النووي الإيراني.. ما آلية “سناب باك”؟، الشرق، تاريخ النشر: ١٩ ديسمبر ٢٠٢٢، متاح على الرابط: https://share.google/dFdKDSW5JVXsDPZhf

[7] إيران: “الوكالة الذرية” أداة ضغط سياسي للغرب و”سناب باك” بلا شرعية، القاهرة الإخبارية، تاريخ النشر: ١٤ يوليو ٢٠٢٥، متاح على الرابط: https://share.google/j76rOBh0r6h4I”aqC