Striking Iran’s Nuclear Facilities: International Law Scholars Warn of Precedent-Setting Violations

The following text is published in the category of “Open Letters and Statements“. 

 

Noting that the 120 Member States of the Non-Aligned Movement (NAM) ‘categorically condemn and denounce in the strongest terms the wanton, unprovoked, and premeditated heinous attack by Israel against the Islamic Republic of Iran on 13 June 2025’,[1] and that they ‘strongly condemn the deliberate targeting of peaceful nuclear facilities by Israel’,[2] while expressing ‘serious concerns that such attacks and the resulting damage pose formidable risks of radioactive material release, representing severe threats to civilian populations and the environment’;[3]

Recalling the Joint Statement of the 57 Member States of the Organization of Islamic Cooperation (OIC), spanning four continents, which states that the ‘reprehensible attack constitutes a flagrant violation of the Charter of the United Nations, the fundamental principles of international law, including sovereignty, territorial integrity, and the prohibition of the threat or use of force against the territorial integrity of States, while grossly violating fundamental rights, particularly the right to life and the right to health’;[4]

Recalling also the statement of the Member States of the Shanghai Cooperation Organization (SCO), which expresses serious concern and ‘condemns the military strikes carried out by Israel’ as ‘aggressive actions against civilian targets, including energy and transport infrastructure, which have resulted in civilian casualties,’ and characterizes them as a ‘gross violation of international law and the United Nations Charter’;[5]

Considering the assessments of UN Experts that the timing of the strikes – coinciding with diplomatic efforts by Iran and the United States in Muscat to revive the 2015 Iran Nuclear Deal – ‘raises serious concerns about the deliberate undermining of peace initiatives’; and that they ‘unequivocally condemn recent Israeli military attacks against Iran, which have targeted nuclear facilities, energy and military infrastructure, as well as residential and media buildings across multiple locations’, which represent ‘a flagrant violation of fundamental principles of international law, a blatant act of aggression, and a violation of jus cogens norms – peremptory rules of international law from which no derogation is permitted’;[6]

We, the undersigned international law scholars, submit this petition to call attention to the illegality of the June 2025 Israeli aggression against Iran, as well as of the subsequent United States’ strikes on Iranian nuclear sites. We are gravely concerned by the erosion of fundamental norms governing the use of force and the protection of civilians. Drawing on authoritative sources of international law, we demonstrate that Israel’s aggression, through invocation of ‘preventive self-defense’ has no legal foundation under the United Nations Charter and customary international law, that the attacks on Iran’s safeguarded nuclear installation contravened international nuclear and environmental law, and that it violated core principles of international humanitarian law. We caution that the practice of using force to impose agreements upon States contravenes the rules-based international legal order. Such acts produce void and nullified effects that no State may recognize as lawful. We further address the broader implications of these violations for the rule of law and global arms-control and disarmament regimes. The findings of this petition rely on treaties, UN General Assembly and Security Council resolutions, the jurisprudence of the International Court of Justice, IAEA resolutions, and academic commentary. The gravity of the issues involved calls for clear-headed legal analysis by the international community.

I. The Prohibition on the Use of Force under International Law

a. Article 2(4) of the UN Charter:

Article 2(4) of the UN Charter enshrines the obligation of all Members to refrain from the ‘threat or use of force against the territorial integrity or political independence of any state.’[7] The International Court of Justice considers the prohibition on the use of force under Article 2(4) of the UN Charter to constitute both an obligation under customary international law[8] and what it has characterized as ‘a cornerstone of the United Nations Charter’.[9] This prohibition is widely recognized in State practice and by the overwhelming majority of international law scholars as possessing a jus cogens or peremptory character from which no derogation is permitted.[10] Further, to highlight the importance of such an obligation it is beneficial to recall that, under the Rome Statue of the International Criminal Court, this act is defined as an ‘act of aggression’ which means the ‘use of armed force by a State against the sovereignty, territorial integrity or political independence of another State, or in any other manner inconsistent with the Charter of the United Nations.’[11]

As articulated by the UN International Law Commission in its Draft Articles on State Responsibility, all States are obligated to cooperate in bringing to an end a serious breach by any State of an obligation arising under a peremptory norm of general international law.[12] Also, States shall not to recognize as lawful any situation created by the use of force.[13] The duty of non-recognition was affirmed by the ICJ in its Advisory Opinion on Construction of a Wall, where the Court held that – as a corollary to the prohibition of the use of force – any measures resulting from the threat or use of force are illegal and must not be recognized as lawful by other States.[14]

The articulation by the U.S. President Donald Trump that ‘Iran should have listened to me […] I gave them a 60-day warning and today is day 61 […] They should now come to the table to make a deal before it’s too late,’[15] exemplifies an impermissible policy of coercive diplomacy. Such rhetoric amounts to ‘a blatant and direct threat of force, used to compel another state to […] make substantial political concessions (not required by law), would have to be seen as illegal under article 2(4) [of the UN Charter].’[16]

This kind of policy – predicated on unilateral threat and use of force – constitutes a null and void act under international law. It produces no legal effect and cannot legitimize the subjugation of another State’s sovereign will. More broadly, such actions pose a serious threat to the rule of law in international relations, fostering instability, impunity, and a return to the law of force over the force of law. If left unchecked, this approach risks hollowing out the normative framework of the UN Charter and emboldening other actors to similarly disregard international legal obligations, thereby precipitating a regression in global peace and security.

b. Absence of a Legitimate Self-Defense Justification:

In the Security Council meeting held on 13 June 2025 concerning the ‘Israeli Air Strikes on Iran’, the representative of Israel purported to justify the attacks as acts of ‘self-defense’ and claimed that Iran had ‘enriched uranium to a level with no civilian justification; obstructed inspectors and destroyed monitoring equipment; developed trigger mechanisms, detonation systems and warhead plans; actively recruited more nuclear scientists; and made false concessions during extended negotiations.’[17]

Bearing in mind that the head of the International Atomic Energy Agency, Rafael Grossi, acknowledged on 17 June 2025 – just days after the Israeli military campaign and before the  United States strikes on Iranian nuclear sites – that the Agency ‘did not have any proof of a systematic effort [by Iran] to move into a nuclear weapon,’[18] it must be noted that, legally speaking, all the justifications raised by Israel’s representative fail to meet the threshold required under international law to lawfully invoke the right of self-defense.

As codified in Article 51 of the United Nations Charter, the use of force in self-defense is permissible only in response to an actual armed attack.[19] International law does not recognize a right to preventive or pre-emptive self-defense based merely on speculative or potential future threats. In one of the earliest commentaries on the UN Charter, it was observed that:

“Abuses of the right of self-defence were in the past facilitated by the theory that self-defence was justified in the face not only of actual, but also of threatened, aggression. The Charter does not admit self-defence against a threat. There must be an actual armed attack.”[20]

More recently, H.P. Aust expressed in his commentary on Article 51 of the United Nations Charter that:

“The interpretation of Art. 51 as being an exclusive regulation of the right of self-defence, has been confirmed by State practice and by the ICJ. In its Nicaragua judgment the ICJ proceeded from the assumption that the existence of an armed attack is a conditio sine qua non for the exercise of the right to individual and collective self-defence.”[21]

The International Court of Justice has repeatedly reaffirmed that Article 51’s exception to Article 2(4) applies only where an armed attack has occurred. In its 1986 judgment in the Nicaragua v. United States of America case, for example, the ICJ emphasized that self-defense lies outside the Charter’s prohibition of use of force solely to meet a genuine, present armed aggression, not hypothetical future threats:

“In the case of individual self-defence, the exercise of this right is subject to the State concerned having been the victim of an armed attack.”[22]

Thus, there is no right of self-defence unless the State has first been the victim of an actual armed attack. However, even if the so-called preventive, anticipatory, or pre-emptive self-defence were to have a basis in international law, the circumstances preceding Israel’s initiation of its military campaign were still insufficient to justify recourse to the use of force.

Those who argue in favour of such pre-emptive self-defence often rely on nineteenth-century State practice, particularly the obsolete Caroline test, according to which a truly imminent threat might justify an anticipatory strike – but still only under exceptional and exigent circumstances, where there exists ‘a necessity of self-defence, instant, overwhelming, leaving no choice of means, and no moment for deliberation.’[23]

Israel and United States’ strikes bore none of those hallmarks; no Iranian attack had occurred, nor was one demonstrably imminent. Leading scholars and States reject a broad doctrine of preventive or pre-emptive use of force; to the contrary, UN resolutions have repeatedly condemned any unilateral aggression under the guise of self-defense.[24] Therefore, Israel’s strike cannot be justified as self-defense and thus contravened the UN Charter’s jus ad bellum regime.

II. Potential Breaches of International Humanitarian Law

a. Attacks on Nuclear Facilities:

Nuclear reactors, installations, and enrichment plants contain radioactive materials, making attacks on these sites extraordinarily dangerous. Additional Protocol I to the Geneva Conventions (1977) on laws applicable in international armed conflicts, specifically prohibits targeting facilities like dams and nuclear power stations when an attack would release ‘dangerous forces’ and cause civilian harm. According to the article 56 of the Additional Protocol:

“Works or installations containing dangerous forces, namely … nuclear electrical generating stations, shall not be made the object of attack, even where these objects are military objectives, if such attack may cause the release of dangerous forces and consequent severe losses among the civilian population. Other military objectives located at or in the vicinity of these works or installations shall not be made the object of attack if such attack may cause the release of dangerous forces from the works or installations and consequent severe losses among the civilian population.”[25]

The IAEA Director-General has warned that assaults on nuclear installations ‘could result in radioactive releases with grave consequences within and beyond the boundaries of the State which has been attacked.’[26] He rightly cautioned that such attacks risk serious harm to ‘both people and the environment … as well as regional and international peace and security.’[27] In this regard, it is relevant to recall the numerous IAEA General Conference resolutions on the topic of military attacks against nuclear facilities, in particular, GC(XXIX)/RES/444 and GC(XXXIV)/RES/533, which provide, inter alia, that ‘any armed attack on and threat against nuclear facilities devoted to peaceful purposes constitutes a violation of the principles of the United Nations Charter, international law and the Statute of the Agency.’[28]

Israel’s repeated practice to attack nuclear facilities of other sovereign States in the region represents a flagrant violation of international law and a direct assault on the foundations of global non-proliferation efforts. Of particular relevance is Resolution 487 (1981), adopted on 19 June 1981, in which the Security Council:

• ‘Strongly condemn[ed]’ Israel’s aerial strike on Iraqi nuclear installations (7 June 1981);
• Found the attack to be a ‘clear violation of the Charter of the United Nations and the norms of international conduct’;
• Characterized it as ‘a danger to international peace and security’, warning that it could ‘explode the situation in the region, with grave consequences for the vital interests of all States’; and
• Further determined that the strike ‘constitutes a serious threat to the entire safeguards regime of the International Atomic Energy Agency, which is the foundation of the Treaty on the Non-Proliferation of Nuclear Weapons.’[29]

From another point of view, military strikes on nuclear installations represent a clear violation of international humanitarian law due to their catastrophic and indiscriminate environmental consequences. The customary and treaty international law explicitly safeguards the natural environment and ‘installations containing dangerous forces’ – prohibiting attacks that risk causing ‘widespread, long-term and severe damage.’[30]

Beyond the legal implications, such actions recklessly endanger civilian populations and the environment, with catastrophic consequences: A deliberate attack on nuclear infrastructure risks widespread radioactive contamination, exposing civilian populations to acute and long-term health hazards, including elevated cancer incidence, genetic mutations, and severe birth defects. The resulting public health emergency could persist for generations, necessitating prolonged medical interventions and mass displacement. Nuclear fallout could precipitate ecosystem collapse, with irreversible damage to agricultural lands, freshwater supplies, and biodiversity. Contaminated zones may remain uninhabitable for decades, exacerbating food insecurity and economic destabilization in the region. Radiation dispersion does not adhere to political boundaries; neighboring States could face secondary contamination, implicating broader regional stability and triggering cross-border humanitarian and legal disputes.

Given these ramifications, such military actions not only breach cardinal principles of UN Charter and international humanitarian law but also directly contravene the core tenets of international environmental law.

b. Protection of Civilians

A core principle of international humanitarian law requires parties to an armed conflict to protect ‘the civilian population and civilian objects and establishes the distinction between combatants and non-combatants; States must never make civilians the object of attack and must consequently never use weapons that are incapable of distinguishing between civilian and military targets.’[31] Civilians shall ‘enjoy general protection against the dangers arising from military operations’[32] and parties must ‘distinguish at all times between the civilian population and combatants.’[33] Israel’s strike reportedly targeted Iranian military or nuclear personnel and simultaneously struck civilian and residential, according to credible reports. Such conduct violates the distinction rule: civilian family members and nearby homes or facilities are not military objects and must not be made the object of attack. Article 51(2) of Protocol I expressly forbids ‘acts or threats of violence’ of any kind against civilians.[34]

The deliberate or reckless killing of civilians and destruction of civilian infrastructure is a grave breach under the Fourth Geneva Convention and constitutes a war crime under customary international law.[35] In this case, striking at least partly civilian areas and family dwellings is inconsistent with any notion of lawful targeting. It echoes the prohibition against collective punishment and terrorizing the civilian population. Such actions undermine the very purpose of international humanitarian law, which is to limit suffering in conflict.[36]

III. Broader Implications for the International Legal Order

Whatever military objective the Israelis claimed, co-locating such an attack in civilian spaces and striking non-combatants with lethal force breaches this core prohibition. The June 2025 attacks on Iran transcend a bilateral dispute; these strike at the bedrock of international law:

First, the invocation of anticipatory or pre-emptive self-defense as justification for cross-border armed aggression erodes the Charter’s prohibition on force. If allowed, it would empower States to act as judge, jury and executioner based on perceived future threats, undermining collective security.

Secondly, the IAEA and UN have long sought to contain nuclear competition through diplomacy and law. Noting furthermore that Israel has not adhered to the Treaty on the Non-Proliferation of Nuclear Weapons, the joint Israel-United States strikes on Iran’s nuclear facilities constituted both a treaty violation and a blow to the credibility of international non-proliferation regimes. Such behaviour sends a catastrophic signal that nuclear accords can be overturned by force, incentivizing other States to flout arms-control commitments under threat.

Thirdly, these incidents undermine the norm of peaceful dispute resolution. Rather than exhausting lawful avenues (such as complaints to the UN Security Council or IAEA fact-finding), Israel resorted to military action. This contravenes Article 2(3) of the UN Charter, which obligates States to settle disputes by peaceful means.

Fourthly, the strikes have enormous implications for humanitarian and environmental norms. Attacks on nuclear facilities revive fears of radioactive pollution and long-term ecological catastrophe. In an era of growing environmental consciousness, such actions flout the developing principle that warfare must not cause ‘widespread, long-term and severe’ environmental damage.

Finally, the attacks set a perilous precedent for civilian protection. If a State can lawfully attack or kill civilians in another State claiming security interests, the entire corpus of international humanitarian law is trivialized. It invites retaliatory measures and escalates conflicts, as the victims may conclude that only reciprocal force can protect their rights. Worse, it encourages a slide toward open conflict in regions with unresolved tensions, eroding confidence in the UN system.

Conclusion and Appeal

For the reasons above, it is our firm conclusion that Israel’s June 2025 aggression against Iran and United States’ strikes on Iranian nuclear sites violated fundamental rules of international law. The preventive self-defense justification is legally invalid, the attacks contravened treaty obligations and IAEA safeguards, and these breached the IHL rules on distinction, proportionality, and civilian protection.

We do not express opinions on the merits of Iran’s policies; rather, we simply apply relevant principles and rules of international law. Under the UN Charter and customary international law, States must refrain from unlawful use of force, protect civilian populations, and respect nuclear safety and arms-control regimes. These principles exist for the sake of international peace, predictability, and humanity.

We, the undersigned legal scholars, respectfully urge States and international institutions to reaffirm these norms. We call on relevant bodies – the United Nations, the IAEA, and the international community at large – to condemn these grave breaches of the law. Upholding the rule of law is essential to preventing the very conflicts that such illegal attacks only exacerbate. Let this petition serve as a scholarly affirmation that neither might nor fear of future threats can override the clear limits of international law. For the sake of future peace and stability, all States must heed the Charter’s mandate and the laws of armed conflicts.

Signatories (in individual capacity) as of 1 July 2025:

Pouria Askary, Associate Professor of International Law, Allameh Tabataba’i University of Tehran, Iran

Olivier Corten, Professor of international law, Université libre de Bruxelles, Belgium

Pierre-Emmanuel Dupont, Senior Lecturer in international law, Institut Catholique de Vendée, France

Salah F. Al Jabery, Chairholder of the UNESCO Chair for Genocide Prevention studies in the Islamic world at University of Baghdad, Iraq

Yoshiko Kurita, Professor, Chiba University, Japan

John Laughland, Senior Lecturer, Faculty of political science and history, Institut Catholique de Vendée, France

Said Mahmoudi, Professor emeritus of international law, Stockholms University, Sweden

Rafaëlle Maison, Professor of international law, Université Paris Saclay, France

Chantal Meloni, Associate Professor of international criminal law, Universitá degli Studi di Milano, Italy

Mohsen Mohebbi, Faculty Member, Islamic Azad University, Science and Research Branch, Iran

Keiko Sakai, Professor, Department of Law, Faculty of Law, Politics and Economics, Chiba University, Japan

Axel Schönberger, University of Bremen, Germany

Katariina Simonen, Adjunct Professor, University of Helsinki, Finland, and Pugwash Council/Pugwash Conferences on Science and World Affairs

Ali Asghar Soltanieh, former Iran Representative to the IAEA (1982-87; 2006-13), President of the Vienna International Institute for Middle East Studies

Alfred M. de Zayas, Professor, Geneva School of Diplomacy, Switzerland

 

Persons wishing to sign the statement can send an email to its initiator and author, Pierre-Emmanuel Dupont, at petitioniran2025@gmail.com.

 

End Notes

[1] Chair of the Coordinating Bureau of the Non-Aligned Movement, The Communiqué of the Non-Aligned Movement on the Recent Heinous Attack of Israel Against the Islamic Republic of Iran (13 June 2025) [1].

[2] Ibid [2].

[3] Ibid.

[4] Permanent Observer Mission of the Organization of Islamic Cooperation to the United Nations, ‘The Joint Statement of the Organization of Islamic Cooperation on the Recent Heinous Attack of Israel Against the Islamic Republic of Iran, UN Doc OIC/NY/25/P/61 (16 June 2025) [3].

[5] Shanghai Cooperation Organization, Statement of the Shanghai Cooperation Organization Regarding Military Strikes on the Territory of the Islamic Republic of Iran (14 June 2025).

[6] United Nations Human Rights, ‘UN Experts Condemn Israeli Attack on Iran and Urge End to Hostilities’ (20 June 2025).

[7] Charter of the United Nations, Art. 2(4).

[8] Military and Paramilitary Activities in and against Nicaragua (Nicaragua v United States of America) (Judgments) [1986] ICJ Rep 14, 146 [292].

[9] Armed Activities on the Territory of the Congo (Democratic Republic of the Congo v Uganda) (Judgment) [2005] ICJ Rep 168, 223 [148].

[10] Oliver Dörr and Albrecht Randelzhofer, ‘Article 2(4)’ in Bruno Simma et al (eds), The Charter of the United Nations: A Commentary (Oxford University Press, 4^th edition, 2024) 229-30.

[11] Rome Statute of the International Criminal Court, opened for signature 17 July 1998, 2187 UNTS 90 (entered into force 1 July 2002) art 8 bis (2).

[12] Responsibility of States for Internationally Wrongful Acts, GA Res 56/83, UN Doc A/RES/56/83 (28 January 2002, adopted 12 December 2001) art 40(1).

[13] Ibid art 41(2)

[14] Legal Consequences of the Construction of a Wall in the Occupied Palestinian Territory (Advisory Opinion) [2004] ICJ Rep 136, 171 [87], 196 [146].

[15] Betsy Klein et al, ‘Trump warns Iran to agree to a deal before there is nothing left’ (13 June 2025) CNN. available at: https://www.cnn.com/2025/06/12/politics/trump-israel-iran-strike

[16] Oscar Schachter, ‘The Right of States to Use Armed Force’ (1984) 82(5) Michigan Law Review 1620, 1625.

[17] UN SC, 9936^th Meeting, UN Doc S/PV.9936 (13 June 2025). available at: https://press.un.org/en/2025/sc16087.doc.htm

[18] Christiane Amanpour, ‘Interview with International Atomic Energy Agency Director General Rafael Grossi’ (17 June 2025) CNN. available at: https://transcripts.cnn.com/show/ampr/date/2025-06-17/segment/01

[19] Charter of the United Nations, Art. 51.

[20] Norman Bentwich and Andrew Martin, A Commentary on the Charter of the United Nations (Routledge, 1^st edition, 1950) 107.

[21] Helmut Philipp Aust, ‘Article 51’ in Bruno Simma et al. (eds), The Charter of the United Nations: A Commentary (Oxford University Press, 4^th edition, 2024) 1769-1820.

[22] Military and Paramilitary Activities in and against Nicaragua (Nicaragua v. United States of America) (Judgment) [1986] ICJ Rep 14, 103 [195].

[23] Hunter Miller, ‘British-American Diplomacy: The Caroline Case’ (Documents in Law, History and Diplomacy, Yale Law School, 2025).

[24] Territorial integrity of Ukraine, GA Res 68/262, UN Doc A/68/L.39 and Add.1 (1 April 2014, adopted 27 March 2014).

[25] Protocol Additional to the Geneva Conventions of 12 August 1949, and relating to the Protection of Victims of International Armed Conflicts (Protocol I), opened for signature 8 June 1977 (entered into force 7 December 1978), Art. 56(1).

[26] IAEA, ‘Statement on the Situation in Iran’ (13 June 2025). available at:  https://www.iaea.org/newscenter/statements/statement-on-the-situation-in-iran-13-june-2025

[27] Ibid.

[28] Protection of Nuclear Installations Devoted to Peaceful Purposes Against Armed Attacks, GC 34, IAEA Doc GC(XXXIV)/RES/533 (October 1990, adopted 21 September 1990) 1 [a]; see also: Protection of Nuclear Installations Devoted to Peaceful Purposes Against Armed Attacks, GC 29, IAEA Doc GC(XXIX)/RES/444 (27 September 1985) 1 [2].

[29] Resolution 487 on the Israeli Military Attack on Iraqi Nuclear Facilities, Sc Res 487, UN Doc S/RES/487 (19 June 1981).

[30] Additional Protocol I, supra note 25, arts. 55-58; ICRC, ‘Rules of Customary International Law’, Rule 42. available at: https://ihl-databases.icrc.org/en/customary-ihl/v1/rule42

[31] Legality of the Threat or Use of Nuclear Weapons (Advisory Opinion) [1996] ICJ Rep 226, 257 [78].

[32] Additional Protocol I, supra note 25, art. 51 (1).

[33] Prosecutor v. Kordic and Cerkez (Judgment) (International Criminal Tribunal for the Former Yugoslavia, Appeals Chamber, Case No. IT-95-14/2-A, 17 December 2004) [54].

[34] Additional Protocol I, supra note 25, art. 51 (2).

[35] Kordic and Cerkez, supra note 33, para. 76.

[36] Prosecutor v. Brdjanind (Judgment) (International Criminal Tribunal for the Former Yugoslavia, Trial Chamber, Case No. IT-99-36-T, 1 September 2004) [591].