Calls for States to take “sanctions” against Israel have grown in number and strength in recent weeks (e.g., here). Such calls take place within the context of Israel’s manifold violations of international law, progressively worse conditions for those in Gaza, and escalating extremist settler violence in the occupied West Bank. Certain States, such as Colombia and Belgium, have already taken measures against Israel in response. The seemingly increasing acceptability amongst some States of using unilateral sanctions against Israel raises two fundamental questions for international law: what can States do? And, what must they do? This article sets out a framework for how these questions can be answered.
After briefly addressing the difficulties with defining what constitutes a “sanction,” this article examines existing and proposed measures against Israel, sets out the international legal framework for unilateral sanctions (what States can do), before analyzing how this framework influences States’ obligation to prevent genocide (what States must do). I argue that, under the current circumstances, at least some of the proposed sanctions are required for States to fulfill the obligation to prevent genocide.
This legal analysis is largely restricted to States. Its findings, however, remain (partially) applicable to international organizations (IOs), such as the European Union (EU), by analogy.
Defining “Sanction”
The term “sanction,” despite having clear legal connotations, is not defined in international law. Several definitions and approaches have been proposed and debated, and the term has been used to describe widely different measures (see Cameron and Moiseienko). In many ways, whether a certain measure is a “sanction” is very much in the eye of the beholder. Ruys identifies three dominant definitional approaches: sanctions are either measures 1) taken in response to a purported violation of international law; 2) created by IOs against their members; or 3) of a certain character – typically economically coercive, such as asset freezes and trade embargoes. In general, sanctions are understood as not constituting a use of force under international law, despite their coercive nature (see Ronzitti).
The ongoing definitional debate on sanctions is a long and intractable one and thus it is not my intention to delve into it in this article (see further Ruys; Bogdanova, p. 60). Moreover, a strict definitional approach is not required to answer what can, and what must, be done by States in the Israel-Palestine context. “Sanction” is therefore understood intentionally broadly here to include all non-forcible measures taken in response to a potential or purported violation of international law, largely similar to the first definitional approach identified by Ruys. Owing to the current inaction of the United Nations Security Council (UNSC) relating to Israel-Palestine, the measures discussed here are those known as “unilateral sanctions.” These are sanctions taken by States (or IOs) without authorization from the UNSC (for more discussion on this, see Thouvenin).
Existing and Proposed Measures
Some (mostly Western) States and the EU have already created targeted sanctions – typically involving an asset freeze and travel ban on individuals and entities – in the Israel-Palestine context. Initially, several States and the EU sanctioned the leaders and funders of Hamas and related groups in response to the 7 October attacks (e.g., here and here). More recently, a number of Israeli extremist settlers and groups were targeted by the EU and a number of States (for an analysis, see van den Herik). Furthermore, two Israeli Government Ministers, Itamar Ben-Gvir and Bezalel Smotrich, were sanctioned in June 2025 by an informal coalition of States (the United Kingdom (UK), Australia, Canada, New Zealand, and Norway). Additional States, such as the Netherlands, have since replicated these measures. According to the UK’s listing, the Ministers were sanctioned for their “repeated incitement of violence against Palestinian civilians.” That being said, the majority of these States and the EU currently appear hesitant to target Israel directly. For example, the UK’s listing of the Israeli Ministers emphasizes the UK’s strong links with Israel and specifies (quite peculiarly) that the conduct that each Minister was targeted for was carried out “in his personal capacity.”
Nevertheless, certain other States have begun to create measures directly against Israel. Most notably, 13 States, acting under the auspices of “The Hague Group,” agreed in July 2025 to take several measures, including a ban on providing or transferring arms as well as preventing “public institutions and public funds… from supporting Israel’s illegal occupation of the Palestinian Territory.” Several of those States had already previously taken significant measures against Israel, including Türkiye’s total export and import ban and Colombia’s halting of coal exports. In addition, several individual EU Member States – acting independently owing to current disagreement at EU level regarding sanctions on Israel – have taken measures, including Slovenia’s total weapons export and import ban, Germany’s particularly notable partial halt to weapons exports, as well as the creation of multiple measures by Belgium and Spain.
In addition, various further-reaching sanctions proposals have been made. Francesca Albanese, the UN Special Rapporteur on the Occupied Palestinian Territories, has called for all States to “impose sanctions and a full arms embargo on Israel” as well as “suspend or prevent all trade agreements and investment relations, and impose sanctions, including asset freezes, on entities and individuals involved in activities that may endanger the Palestinians” (para. 94(a) and (b)). Similarly, a group of former EU ambassadors and diplomats demanded a range of measures in July 2025, including an end to “all preferential commercial arrangements for Israel” under the EU-Israel Association Agreement as well as the creation of targeted sanctions on those considered responsible for committing international crimes, including Israeli Ministers. Subsequent calls have demanded even stronger action at EU level (for further analysis on potential EU sanctions, see Evans and Molina-Clemente). Most recently, the Independent International Commission of Inquiry on the Occupied Palestinian Territory, including East Jerusalem, and Israel (CoI) recommended that States impose sanctions “against the State of Israel and against individuals and corporations that are involved in or facilitating the commission of genocide or incitement to commit genocide” (para. 257(d); see also paras. 257(b) and (c)).
What Can be Done? The Legal Framework Applicable to Unilateral Sanctions
As can be seen, the existing and proposed measures vary in form and intensity. Importantly, the specific legal basis for each measure is typically not indicated by those creating or proposing them. Therefore, it is important to set out the applicable legal framework to examine what States can do. Addressing this before considering what States must do is crucial as a measure’s legality in the abstract determines whether it can be used to fulfill certain obligations (e.g., the obligation to prevent genocide).
As an important starting point, the very legality of unilateral sanctions under international law is contested. Some States and commentators argue that unilateral sanctions are illegal in all circumstances owing to either 1) a customary international law prohibition, or 2) because they violate the principle of non-intervention. For such States, they might answer the question of “what can be done?” – at least regarding sanctions – with “nothing.” Without delving into these debates, it is nevertheless doubtful whether an absolute prohibition of unilateral sanctions currently exists (see Tzanakopoulos; contra, Mohamad). Rather, a unilateral sanction’s legality will depend on its character and the context of its imposition (e.g., see Milanovic). Hence, a case-by-case legal analysis is required.
Firstly, if a sanction does not violate an international legal obligation owed by the State creating the sanction, the measure will qualify as a “retorsion.” Such measures are typically understood as unfriendly but legally permissible. In simple terms, any measure that is not illegal under international law is permissible, even if coercive in nature. Retorsions can include, depending on the circumstances, arms embargoes as well as legally permissible suspensions of treaties (see Giegerich).
If a sanction does violate an international legal obligation owed to the targeted State, it may still be justified as a lawful countermeasure in certain circumstances. Under the International Law Commission’s Draft Articles on Responsibility of States for International Wrongfully Acts (ARSIWA), which are considered to largely reflect customary international law, countermeasures are acts of self-help that States injured by an internationally wrongful act can use to induce the responsible State to fulfill its international legal obligations, including to provide reparation (ARSIWA, Article 49). According to ARSIWA, countermeasures must respect several substantive and procedural requirements to be lawful (Articles 49-53). Importantly, countermeasures must “as far as possible” be reversible, cannot be in violation of peremptory norms (such as the prohibition of the use of force), and must be proportionate to the injury suffered (see Paddeu). In addition, measures taken against non-State entities or individuals cannot be justified as countermeasures (see Hofer, pp. 189-191). Countermeasures are, nevertheless, controversial as they typically depend on the purportedly injured party self-determining that a violation of international law has occurred.
In situations where States are not directly injured by a violation of international law, but the violation in question relates to an obligation owed erga omnes (partes), some States and scholars argue that sanctions can be justified as “third-party countermeasures” against the State responsible (e.g., see Dawidowicz). For example, many of the sanctions created against the Russian Federation following the full-scale invasion of Ukraine have been conceptualized as third-party countermeasures. In principle, largely the same substantive and procedural rules would apply as regular countermeasures (see Dawidowicz, Chapter 6). Nevertheless, whether third-party countermeasures are permitted under international law is a deeply debated issue (e.g., see Hofer; ARSIWA, Article 54).
Finally, if a sanction does not (or no longer) constitutes a retorsion or lawful countermeasure then it likely constitutes an internationally wrongful act (with no other applicable circumstances precluding wrongfulness as set forward in ARSIWA, Part I, Chapter V), therefore giving rise to the obligations of cessation, non-repetition, and reparation (e.g., ARSIWA, Articles 30 and 31).
Therefore, at the very least, States are entitled to create retorsions and, if directly injured, lawful countermeasures against Israel. The boundary between retorsions and countermeasures is not a fine line and will depend largely on each State’s particular (legal) relationship with Israel. While this might decrease the relevance of direct countermeasures in this context, it is important to note that many far-reaching measures can be conceptualized as retorsions.
What Must be Done? The Obligation to Prevent Genocide
The above legal framework demonstrates what measures States can take in response to Israel’s violations of international law. However, the nature of some of Israel’s (alleged) violations gives rise to specific obligations on third States, potentially shifting the sanctions question from what can be done to what must be done. This section focuses on the obligation to prevent genocide, owing to its particularly far-reaching nature. Other third-party obligations, including the obligation to ensure respect for international humanitarian law (IHL) (in general, see Zwanenburg) and the obligation of non-recognition of the unlawful presence of Israel in the Occupied Palestinian Territory (Advisory Opinion on the Occupied Palestinian Territory, paras. 280 and 285(7)), may also require the creation of sanctions under certain circumstances, but those issues are not addressed here.
To begin with, States at risk of complicity in violations of international law carried out by Israel, including relating to genocide, must take measures to avoid that complicity (ARSIWA, Article 16). Many measures that could be described as sanctions – in particular, the cessation of ongoing arms sales to Israel – would therefore be required simply to avert complicity (for more on the obligation not to be complicit in genocide, see Pietropaoli, pp. 11-13).
Moving further, under the Genocide Convention (Article I) and customary international law (Reservations to the Genocide Convention Advisory Opinion, p. 23), all States have an obligation to prevent genocide. In the Bosnia Genocide case, the International Court of Justice (ICJ) stated that the obligation is triggered when a State “learns of, or should normally have learned of, the existence of a serious risk that genocide will be committed” (para. 431). As such, the obligation is triggered even if genocide has not (yet) been committed (ibid.). The ICJ’s provisional measures orders in the South Africa v. Israel proceedings, in addition to the subsequent deterioration of conditions in Gaza, arguably indicate that the obligation for third States to prevent genocide has been triggered (see CoI, para. 249; de Hoon and Sluiter, pp. 3-5).
The obligation to prevent genocide is due diligence in nature, meaning that a State “does not incur responsibility simply because the desired result is not achieved; responsibility is however incurred if the State manifestly failed to take all measures to prevent genocide which were within its power, and which might have contributed to preventing the genocide” (Bosnia Genocide case, para. 431). Importantly, the obligation requires States “to employ all means reasonably available to them, so as to prevent genocide so far as possible” (ibid., para. 430). A State’s “capacity to influence effectively” those “likely to commit, or already committing, genocide” is determined by, among others, “geographical distance” and the “strength of the political links” with “the main actors in the events” (ibid., para. 430). Furthermore, States must take action even if they alone do not have the capacity to fully prevent the potential genocide in question (ibid., para. 431). Significantly, measures taken to fulfill the obligation to prevent must be “within the limits permitted by international law” (ibid., para. 430, emphasis added).
Considering that the obligation to prevent genocide has arguably been triggered, and having established that at least some unilateral sanctions are permissible under international law, it is therefore conceivable that certain States might in certain circumstances be required to take legally permissible unilateral sanctions to fulfill the obligation to prevent genocide. Determining when sanctions become obligatory again requires a case-by-case analysis, involving several considerations. As established above, States have a certain discretion in how to fulfill the obligation to prevent, taking into account, for example, their specific capacities as well as their particular relationship with Israel (for a helpful overview on this point, see the Dutch Advisory Committee on Public International Law (CAVV)’s recent report, pp. 7-9; summary in English, here). If States are genuinely able to leverage diplomatic or other less-intrusive means to seek a change in behavior, then sanctions may therefore not be required to satisfy the obligation to prevent genocide. Furthermore, it is not a given that a particular sanction will contribute to the prevention of genocide; in fact, some sanctions have been criticized for their ineffectiveness (see Giumelli). Nevertheless, considering that where diplomatic efforts have been attempted they have failed to put an end to the situation, and taking into account the potential capability of certain sanctions to prevent or interdict genocide and other serious violations of international law (see, e.g., Jia; Bastaki), many of the measures proposed – such as further arms embargoes on Israel and additional sanctions on those inciting and perpetrating international crimes against Palestinians – have arguably moved from optional to obligatory, to the extent that they comply with international law.
Although each State will need to independently assess what the obligation to prevent genocide requires of them, legally permissible unilateral sanctions should not only be viewed as an option, but in some cases a legal necessity. This finding applies not only to the obligation to prevent genocide and averting complicity with Israel’s violations of international law, but potentially also for other obligations not addressed in this article, such as the obligation to ensure respect for IHL.
Conclusion
This article has shown that not only can States take certain sanctions against Israel, but that they arguably must in order to satisfy the obligation to prevent genocide. With the situation in Gaza, in particular, continually deteriorating, States must seriously and carefully assess the measures they may be required to take to fulfil their international legal obligations.