The Siege Within

Israel has blocked humanitarian aid from entering Gaza since the end of a ceasefire in March, throwing the territory into what is believed to be the worst humanitarian crisis in nearly 20 months of war.

This deepening crisis, coupled with Israel’s ban on UNRWA operations, has drawn increasing international scrutiny. Following an initiative of Norway in connection with Israel’s ban of UNRWA, the United Nations General Assembly adopted Resolution 79/232, requesting the International Court of Justice (ICJ) to render an advisory opinion. In this context, the ICJ concluded public hearings on 2 May 2025, focusing on Israel’s obligations with respect to the presence and activities of the United Nations, other international organizations, and third States within the Occupied Palestinian Territory (OPT).

This comment analyzes the specific, and often contested, mental requirements –particularly the intent of a State to starve civilians – that govern the attribution of State responsibility under the prohibition against starvation as a method of warfare in international humanitarian law (IHL). In support of this analysis, it draws on the written and oral submissions of States during the ICJ hearings, as well as national military manuals from countries such as Australia, Canada, Denmark, France, Germany, New Zealand, the UK, and the US – selected based on availability and contemporaneity to reflect their State practice.

Israel’s Obligations towards the Palestinian People: Contested Intent Behind Starvation

Under Article 54 of Additional Protocol I, which prohibits warfare methods aimed at starving the civilian population, Israel is obligated to refrain from using starvation as a method of warfare against the Palestinian people.

Unlike Article 8(2)(b)(xxv) of the Rome Statute – which explicitly provides that “intentionally” using starvation of civilians as a method of warfare constitutes a war crime and allows for the interpretation of “intentionally” with reference to Article 30(2) – Article 54 of Additional Protocol I does not elaborate on the mental element attributable to States when engaging in starvation as a method of warfare.

While methods of warfare resulting in the starvation of civilians do not, per se, prohibit Israel from conducting siege or naval blockade (see e.g. Henckaerts/Doswald-Beck pp. 188-189), the issue remains complex. The main controversy – highlighted in this post – centers on whether, in cases where a State refuses or obstructs humanitarian assistance, a specific intent to starve the civilian population must be proven. This determination is crucial to assessing whether such conduct constitutes a prohibited method of warfare and gives rise to State responsibility for violations of IHL.

The classical view holds that siege is not prohibited even if they result in starvation, provided that their purpose is to achieve a military objective rather than to starve the civilian population (see Oxford Guidance, para. 95). Some even argue that siege is only unlawful if the starvation of civilians is its sole or primary purpose (see San Remo Manual, Art. 102(a); Air and Missile Warfare Manual, Art. 157(a)). In contrast, Israel’s military manual appears to hold that the refusal or obstruction of humanitarian assistance may automatically be considered a method of warfare aimed at starving civilians, without the need to assess intent (see van Steenberghe, p. 1007).

Intent in State Practice: the Evolution of Customary International Law

So far, it remains unclear when the refusal or obstruction of humanitarian assistance may amount to starvation as a prohibited method of warfare under international humanitarian law and entail State responsibility. State practice and opinio juris – particularly as reflected in national military manuals and States’ participation in the most recent ICJ advisory proceedings – may provide further clarification on this issue.

As formal instruments regulating armed forces and conduct during armed conflict (see Bothe, p. 156), national military manuals reflect States’ interpretations of international legal norms and are considered “official publications” evidencing opinio juris by the International Law Commission (see UN Doc. A/73/10, p. 141), while also serving as a valuable tool for identifying State practice, as recognized by the ICTY Appeals Chamber (see Prosecutor v. Duško Tadić, para. 99).

On the one hand, a review of the selected national military manuals indicates that all of them endorse the position that siege is not prohibited even if they result in starvation, provided that their purpose is to achieve a military objective rather than to starve the civilian population (see Australia, para. 6.65; Canada, para. 850; Denmark, pp. 418, 564; France, pp. 131, 161; Germany, para. 1150; New Zealand, para. 8.8.26, 10.5.4, 17.5.4; UK, para. 5.20.1, 13.9.3, 13.10.2.5, 17.4.1.3, 17.9.2.1; US, para. 5.20.1, 13.9.3, 13.10.2.5, 17.4.1.3, 17.9.2.1). Some States go further, insisting that a siege is only unlawful if its sole or primary purpose is to starve civilians (see Germany, para. 1150; Denmark, p. 564; Australia, para. 6.65; Canada, para. 850; New Zealand, para. 8.8.26).

On the other hand, among all written and oral statements made by States during the ICJ proceedings in the 2025 OPT Advisory Opinion, the majority did not provide a detailed analysis of the specific requirements governing starvation as a method of warfare. Several States simply emphasize that the refusal or obstruction of humanitarian assistance would constitute starvation (see Slovenia, para. 27; Mexico, para. 79; Comoros, para. 109). It is nonetheless noteworthy that a number of statements acknowledge that the prohibition of starvation as a method of warfare requires an intent to starve the civilian population (see League of Arab States, paras. 270, 272; Egypt, para. 273; China, para. 41; Qatar, p. 45; Poland, p. 34). Meanwhile, some States stopped short of explicitly asserting that intent is a necessary element, but nonetheless condemned Israel’s deliberate use of starvation tactics (see Kuwait, p. 50; Bolivia, p. 14; South Africa, pp. 12, 23). While Palestine itself did not explicitly acknowledge that the commission of starvation as a method of warfare requires such intent, it emphasizes in both its written and oral statements that Israel does have the intent to starve the civilian population (written submission of Palestine, paras. 4.76, 4.97; oral submission of Palestine, p. 73). None of these participating States explicitly asserted the view that the mere refusal or obstruction of humanitarian assistance automatically constitutes the use of starvation as a method of warfare, regardless of any intent to starve the civilian population.

Reconciling Intent with Gaza’s Humanitarian Catastrophe

The above analysis demonstrates that current State positions, in general, continue to recognize that the prohibition of starvation as a method of warfare entails a requirement of intent to starve the civilian population. However, such an interpretation of the development of customary international law may undermine the protection of civilians suffering from starvation and appear inconsistent with humanitarian values, particularly given the considerable difficulty in demonstrating such intent of States in most situations, including with respect to Israel’s widely condemned restrictions on relief supplies to the Gazan population (see van Steenberghe, p. 1002), which has led to a grave humanitarian catastrophe of global concern.

Therefore, the authors submit that if intent remains a required element for starvation under Article 54(1) of Additional Protocol I, it might be worth exploring a flexible and broader interpretation of intent within the context of IHL. One possible approach is to draw on Article 30(2)(b) of the Rome Statute, which allows for the recognition of intent when a party is aware that the starvation of civilians may result from the ordinary course of events. If this interpretation is applied to the humanitarian crisis in Gaza, Israel’s intent to starve civilians would be more readily established, as it would be difficult for Israel to deny that it could have foreseen, in the ordinary course of events, that its obstruction of humanitarian assistance would result in thousands of innocent civilians being driven to starvation.

Admittedly, such an interpretative approach may encounter legal difficulties, as it requires determining a State’s intent within a framework originally designed to assess individual intent, which warrants further detailed discussion. Nevertheless, from a humanitarian perspective, such an approach would not only enhance the protection of civilian lives but also uphold the core humanitarian principles of compassion and dignity, ensuring that the suffering of innocent populations is prevented wherever possible.