In January 2009, Israel imposed a far-reaching naval blockade after attempts by the Free Gaza Movement to enter the closed Gaza Strip by sea. While international lawyers have discussed the legality of the naval blockade extensively (see here, here, here and here), its detrimental consequences for Gaza’s marine environment have been largely overlooked. These consequences are less urgent than the human suffering in the current Gaza conflict, but they constitute serious violations of international law and may be irreversible. The International Committee of the Red Cross (ICRC) updated its Guidelines on the Protection of the Natural Environment in 2020 (‘2020 ICRC Guidelines’) and the International Law Commission (ILC) adopted Principles on the Protection of the Environment in Relation to Armed Conflicts in 2022 (‘2022 ILC Principles’) that highlight the fundamental importance of safeguarding the environment in armed conflict.
This post discusses how the naval blockade violates rules of international environmental law and the law of the sea with severe mid- and long-term consequences for Gaza’s marine ecosystem, including the question of international responsibility for such violations. In its 2024 Advisory Opinion on Legal Consequences arising from the Policies and Practices of Israel in the Occupied Palestinian Territory, the International Court of Justice clarified Israel’s obligations as an occupying power in relation to the Palestinian population, particularly regarding international humanitarian law and human rights law. However, an issue that remains unaddressed is whether Israel would also incur shared or exclusive international responsibility when Palestine breaches its international obligations, such as those related to the protection of its marine environment.
The Impact of the Naval Blockade on the Protection of Gaza’s Marine Environment
The protection of the marine environment is enshrined in different provisions of the UN Convention on the Law of the Sea (UNCLOS) to which Palestine acceded in 2015. While Israel is not a party to UNCLOS, many of its provisions constitute customary international law. UNCLOS is mainly designed for peaceful international relations, but as the ICRC notes in its 2020 Guidelines, “other rules of international treaty and customary law protecting the natural environment (including rules of international environmental law, international human rights law, the law of the sea and international criminal law) may continue to apply during international and non-international armed conflicts” (para 24). The 2020 ICRC Guidelines also provide, as a matter of custom, that “[m]ethods and means of warfare must be employed with due regard to the protection and preservation of the natural environment” (Rule 1).
A key feature of UNCLOS is the zonal approach, stipulating the rights and obligations of coastal and other states, including regarding the environment. The entry into force of UNCLOS in 1994 coincided with the 1993 and 1995 Oslo Accords I and II, which do not apply this zonal approach. Among other things, the Accords permit Palestinian fishing activity in a zone extending up to 20 nautical miles from the Gaza coast (Oslo Accord II, Annex I, Article XIV), and they allow Israel to impose further restrictions for security reasons. The Oslo Accords did not recognize Palestine as a sovereign coastal state, but they only constituted a provisional agreement with a view to future “permanent status negotiations”. Palestine’s accession to UNCLOS and its 2019 declaration of maritime zones (including a 12 nautical miles territorial sea, a 24 nautical miles contiguous zone, and an exclusive economic zone and continental shelf of 200 nautical miles) highlighted its claim to statehood.
Nonetheless, Israel’s naval blockade has made it difficult – if not impossible – for Palestine to comply with its obligations under UNCLOS and the customary international law on the protection of the marine environment. Over the past decades, Israel has never fully implemented the 20 nautical miles fishing zone stipulated in the Oslo II Accord. Since 2000, Israel has regularly imposed restrictions on fishing zones, typically enforcing limits between 3 to 15 nautical miles (see here and here), with fishing vessels that venture beyond these points subject to potential engagement by Israeli naval forces maintaining the blockade. These restrictive measures have impeded Palestine from complying with its obligations under Article 61(2) of UNCLOS to “ensure through proper conservation and management measures that the maintenance of the living resources in the exclusive economic zone is not endangered by over-exploitation”. In particular, the increasing confinement of Palestinian fishers to narrow areas of Gaza’s territorial waters has caused environmental harm through the over-exploitation of juvenile fish populations within this limited area—precisely the type of unsustainable resource management that UNCLOS seeks to prevent.
Marine pollution is another direct consequence of the blockade and occupation regime, implicating different legal obligations regarding environmental protection in Gaza’s maritime zones. Gaza’s coastline has been experiencing severe environmental degradation attributable to the continuous discharge of untreated sewage and solid waste, and the presence of weapon-related debris in the water and on the beaches. UNCLOS characterizes this situation as marine pollution, defined in Article 1(4) as “the introduction by man, directly or indirectly, of substances or energy into the marine environment […] which results or is likely to result in such deleterious effects as harm to living resources and marine life, hazards to human health, hindrance to marine activities, including fishing and other legitimate uses of the sea, impairment of quality for use of sea water and reduction of amenities.”
Article 192 of UNCLOS imposes an absolute duty on all states to protect and preserve the marine environment. Article 194 obligates States Parties, “individually or jointly”, to take “all measures….that are necessary to prevent, reduce and control pollution of the marine environment from any source”. Yet, Palestine has been unable to address the pollution and environmental degradation effectively, possibly breaching its obligations to protect Gaza’s marine environment. With the Israeli navy enforcing a strict naval blockade, Palestine lacks physical access to the affected waters. Even basic shoreline remediation efforts are stymied by Israeli occupation, stringent import restrictions imposed by Israel on essential materials and chronic fuel shortages that prevent the operation of wastewater treatment machinery. As the environmental degradation continues unabated, it is estimated to take 10 to 25 years without pollution for the natural flora and fauna to recover from the ongoing chronic sewage pollution of Gaza’s coastal waters.
International Responsibility – Exclusive or shared?
Palestine’s potential violations of its international obligations pertaining to the protection of its marine environment raise the question of its international responsibility, including possible circumstances precluding wrongfulness and remedies (see Principle 9 of the 2022 ILC Principles). As Palestine’s non-compliance is at least partly due to Israel’s naval blockade, Israel, as an occupying power, might also be responsible, either jointly with Palestine or exclusively, for Palestine’s non-compliance.
In general, little guidance exists on the obligations of the occupying power to ensure that the occupied state or territory complies with its international commitments. The ILC’s 2001 Articles on the Responsibility of States for Internationally Wrongful Acts (ARSIWA) regulate the responsibility of a state for the “Direction and control exercised over the commission of an internationally wrongful act” in Article 17. As the ARSIWA commentary to Article 17 (at para 5) explains, “the occupying State is responsible for acts of the occupied State which it directs and controls”. However, although many of the ARSIWA’s provisions have trickled down into the practice of international courts and tribunals (see Book 25 of the UN Legislative Series (2nd ed, 2023), Article 17 has found no relevant mention.
A challenge in applying Article 17 to Palestine’s violations of international law under the naval blockade is that Israel’s direction and control would have to relate to the actual wrongful conduct under consideration. Israel’s “power to interfere in matters of administration internal to” Palestine is not sufficient to establish direction and control (ARSIWA commentary to Article 17, para 6). The narrow maritime space left to Palestinian fishers, the lack of access of coastal access and to the necessary means to address the degradation of Gaza’s marine environment arguably have made it difficult for Palestine comply with its obligations to protect the marine environment. It is questionable, though, whether Israel directed and controlled Palestine’s specific omissions (e.g., the failure to take measures to fresh overfishing of juvenile fish populations) in the meaning of Article 17.
Another condition for the application of Article 17 is that Israel had knowledge of the harmful impact of its naval blockade on Gaza’s marine environment. Given the numerous reports by the UN and news sources (see e.g. here and here), this was likely the case. As provided in Article 17(b), the third condition is that the completed act would have been wrongful had it been committed by the directing and controlling state itself, which implies that Israel would have to be bound by the obligations breached by Palestine. In this context, it is decisive that the rules on the protection of the marine environment and on the environment in armed conflict are customary international law (see e.g. paras 42, 47, and 76 of the 2020 ICRC Guidelines) and thus binding on both Israel and Palestine.
Even if Israel incurred international responsibility for Palestine’s non-compliance based on direction and control, this responsibility would likely be shared with Palestine. As the ILC explains in its commentary to Article 17 (at para 9), “the mere fact that it [in this case, Palestine] was directed to carry out an internationally wrongful act does not constitute an excuse under chapter V of Part One”, i.e. a circumstance precluding Palestine’s wrongfulness (see the Guiding Principles on Shared Responsibility in International Law for a pertinent interpretation of the ARSIWA).
Since 2023, Israel’s control over Palestine’s maritime space has increased significantly, exacerbating the detrimental environmental impacts of the naval blockade. Following the Hamas attacks of 7 October, Israel has implemented a comprehensive prohibition on Palestinian maritime activities, including fishing and any form of sea access. Shortly thereafter, Israel started to unilaterally grant gas exploration licenses for a gas field situated approximately 21 nautical miles off the coast in the eastern Mediterranean Sea, within waters that constitute part of Palestine’s EEZ, highlighting the extent of Israel’s authority over Palestine’s maritime zones and the resources contained therein.
Given the sweeping nature of Israel’s naval blockade since October 2023, Israel could be exclusively responsible for Palestine’s non-compliance with its international obligations under Article 18 of the ARSIWA on “Coercion of another State”. Like Article 17, Article 18 presupposes knowledge by the coercing state, but the coercing state does not have to be bound by the same obligation as the coerced state. Moreover, the ILC adopts a definition of coercion that covers the use of force and non-forcible measures, such as “serious economic pressure”. The decisive criterion is that the coerced state had “no effective choice but to comply with the wishes of the coercing State” (ARSIWA commentary to Article 17, paras 2-3). The ILC notes that coercion functions like “force majeure” under Article 23 of the ARSIWA, which precludes the wrongfulness of the conduct of the coerced state (see para 2 of the ARSIWA commentary to Article 18). If the naval blockade qualified as coercion, Palestine would not incur responsibility for the breach of its international obligations.
Conclusion
Israel’s naval blockade has resulted in widespread harm to Gaza’s marine environment violating fundamental rules across multiple international legal frameworks. The environmental consequences of the blockade will persist long after any potential ceasefire or peace agreement. Marine ecosystems damaged by pollution typically require decades to recover to baseline conditions. Fish stocks depleted through concentrated fishing pressure in restricted zones necessitate years of reduced exploitation to replenish. It is essential to determine international responsibility, including timely remedies, for these largely overlooked violations of international law to preserve the possibility of sustainable development and environmental habitability in a post-conflict Gaza.
