In October 2025, Israel’s seizure of the Marinette—a humanitarian flotilla bound for Gaza—sparked global outrage and reopened the debate on the legality of its long-standing naval blockade. Beyond a single incident, it symbolises the erosion of international maritime law, raising the question: how far can security be invoked to justify actions that defy global humanitarian principles?
AFTAB ALAM | DEAN, FACULTY OF INTERNATIONAL STUDIES |
ALIGARH MUSLIM UNIVERSITY FOR NEWS ANALYTICS
a 5 mins read.
On 3 October, Israeli naval commandos intercepted and seized the Marinette, the final vessel of the 44-ship Global Sumud Flotilla, as it sailed through international waters towards Gaza. This followed the interception of other flotilla vessels on 1 October. The flotilla carried over 500 parliamentarians, lawyers, journalists, and activists united in a desperate bid to deliver humanitarian aid to Gaza’s two million besieged residents. Defiant, the Freedom Flotilla Coalition, the umbrella organisation behind many such missions, launched a similar effort from Italy the very next week.
The seizure of the Global Sumud Flotilla has sparked global condemnation, igniting a fierce debate over its legality under international law. Human rights groups denounce the interception of a humanitarian mission in international waters as a flagrant violation of international law guaranteeing maritime freedom. Colombia has cut diplomatic and trade ties; several European nations have urged respect for the rights of detained crew members; and UN experts have denounced the interceptions as an “illegal abduction” amid growing concern for Gaza’s civilians. Yet Israel defends its actions as necessary security measures, asserting that its naval blockade, enforced since 2009 to thwart weapons smuggling to Hamas, is both lawful and essential. Israel has consistently characterised flotillas seeking to break the Gaza blockade as “propaganda” or “stunts” orchestrated by “terror activists” allegedly linked to Hamas — a claim widely rejected by flotilla organisers, participants, human rights experts, and numerous international governments, with the Swedish activist Greta Thunberg remarking that “nobody would risk their lives for a publicity stunt.”
“Freedom of the seas cannot be suspended by politics or power.” – Maritime Law Scholar, Geneva Institute
A PATTERN OF FORCE AT SEA
This is, however, not an isolated incident. Israel has successfully intercepted almost all aid flotillas bound for Gaza for over a decade, with one exception in 2008. Every attempt since then has been foiled by Israeli forces. The most infamous incident occurred in May 2010, when Israeli commandos stormed the lead ship of the Gaza Freedom Flotilla, the Mavi Marmara, in international waters, killing nine Turkish nationals and injuring dozens. Undeterred by the deadly 2010 raid, the flotilla movement has persisted with remarkable resilience. However, a clear pattern is evident, as subsequent similar efforts 
in 2011, 2015, 2018, and 2021 met the same fate: interception, seizure, and the detention and eventual deportation of activists. This pattern continues unabated. In 2025 alone, Israel intercepted the aid ships Conscience in May, Madleen in June, and Handala in July. These actions clearly demonstrate a consistent Israeli policy: treating every humanitarian flotilla as a security threat to be met with force.
This pattern of seizing aid flotillas flouts the 1982 United Nations Convention on the Law of the Sea (UNCLOS), which governs maritime navigation. UNCLOS designates waters beyond the 12-nautical-mile (19 km) territorial sea as international waters, where all states enjoy unfettered navigational rights. Article 2 of the 1958 Convention on the High Seas and Article 87 of UNCLOS provide that the high seas are open to all states and guarantee freedom of navigation. Furthermore, Article 88 of UNCLOS stipulates that the high seas must be used exclusively for peaceful purposes.
According to Article 92(1) of UNCLOS and Article 6(1) of the 1958 Convention, a vessel on the high seas is, in principle, subject only to the jurisdiction of its flag state. States may not seize vessels in international waters except in narrow circumstances, including piracy, the slave trade, illicit drug trafficking, unauthorised broadcasting, and situations where a vessel is suspected of sailing under a false flag. However, none of these exceptions applies to Israel’s actions against the Sumud Flotilla. Thus, by intercepting the Global Sumud Flotilla 70 nautical miles (130 km) off Gaza’s coast, Israel brazenly violated UNCLOS, trampling the fundamental right to maritime freedom and denying vital aid to a desperate population. It sets a dangerous precedent by allowing states to project their domestic security policies hundreds of miles into international waters.
“A blockade in international waters, absent UN approval, is a perilous precedent.”
THE LAW BREACHED
Israel justifies its actions by invoking the law of naval blockade, arguing that, as a state engaged in an armed conflict with Hamas, it has the legal right to intercept vessels attempting to breach this blockade. This stance, however, rests on a legally tenuous and contradictory foundation. It also raises two critical questions. First, can a state legitimately impose a naval blockade on a territory it is widely considered to control as an occupying power? Second, can such a blockade be enforced without exceptions, prohibiting all civilian humanitarian aid?
Traditionally, a naval blockade, as an act of war, restricts access to ports and coasts under enemy control to prevent vessel traffic from any state. Consequently, an occupying power cannot legally declare war against a territory it already controls. Due to its effective control over Gaza’s borders, airspace, territorial waters, population registry, and the entry and exit of goods, Israel is widely regarded as the occupying power in Gaza — a status disputed by Israel but affirmed by international bodies such as the United Nations, the International Committee of the Red Cross, and the International Court of Justice. The definition of a naval blockade suggests that Israel cannot legally establish or enforce such a blockade on Gaza’s coastline. This interpretation is grounded in customary international law, as reflected in the 1909 London Declaration and the 1913 Oxford Manual, and supported by modern military manuals from Germany, Australia, and the United States.
Furthermore, within the contemporary United Nations framework, a naval blockade is fundamentally considered an act of force and is therefore prohibited under international law. For such a blockade to be considered lawful, it must meet one of two stringent criteria: it must be explicitly authorised by the UN Security Council as a measure to address a threat to international peace and security, or it must be a necessary and proportional act of self-defence under Article 51 of the UN Charter, enacted in response to an ongoing armed attack. Israel’s blockade of Gaza meets neither of these conditions, as it was neither mandated by the Security Council nor a legitimate act of self-defence, as Article 51 applies only in response to an armed attack by one state against another. Israel is not engaged in conflict with another state but rather with Hamas, a non-state resistance organisation.
THE LEGAL VOID
Even if Israel’s naval blockade of Gaza is considered legal, international law imposes stringent limitations on it. A blockade that disproportionately harms civilians and undermines their living conditions is a clear violation of international law applicable during armed conflict. Accordingly, Israel must not cause disproportionate harm to civilians and is obligated to ensure the unimpeded passage of essential humanitarian aid to meet the civilian population’s needs. The Gaza blockade deliberately subjects the Palestinian population to mass starvation, a method of warfare strictly prohibited under Article 54 of Additional Protocol I (AP I) to the Geneva Conventions.
The San Remo Manual on International Law Applicable to Armed Conflicts at Sea (1994) expressly prohibits a blockade if its sole purpose is to starve a civilian population or deny it other objects essential for its survival, or if the damage to the civilian population is, or may be expected to be, excessive in relation to the concrete and direct military advantage anticipated. It further imposes a positive obligation on the blockading state to provide free passage of such foodstuffs and supplies if the civilian population of a blockaded territory is inadequately supplied with essentials.
“When famine is man-made, neutrality is complicity.” – UN Humanitarian Rapporteur, Geneva
GLOBAL RESPONSIBILITY
Likewise, Article 59 of the Fourth Geneva Convention of 1949 mandates occupying powers to permit the free passage of humanitarian aid. The ICRC’s study on customary international humanitarian law further requires parties to a conflict to ensure the rapid and unimpeded delivery of humanitarian relief to civilians in need. Consequently, seizing peaceful vessels carrying such aid directly violates these obligations.
Moreover, a UN-backed IPC panel recently confirmed a famine in Gaza, attributing it to Israel’s “systematic obstruction” of aid. A January 2024 ICJ provisional ruling also mandated Israel to “take immediate and effective measures” to enable humanitarian aid — a demand echoed by UN Security Council Resolutions 2720 and 2728, which call for unimpeded humanitarian access. By these standards, Israel’s blockade of Gaza and its interception of humanitarian vessels are legally untenable. Following the *Mavi Marmara* killings, the Human Rights Council also deemed Israel’s blockade unlawful, its enforcement in international waters illegal, and its use of force disproportionate. These findings remain directly applicable to today’s flotillas.
Israel’s interception and seizure of the Global Sumud Flotilla cannot be justified as lawful enforcement of a naval blockade. It violates freedom of navigation, disregards humanitarian exceptions in blockade law, breaches the Fourth Geneva Convention, defies binding UN Security Council resolutions, and contravenes the International Court of Justice’s January 2024 ruling mandating humanitarian aid access. While Israel, as an occupying power, may inspect vessels to prevent weapons smuggling to Hamas, intercepting flotillas carrying solely humanitarian aid to a famine-stricken population is indefensible. This action undermines the international legal order and sets a dangerous precedent for global humanitarian efforts. What is now needed is to move beyond routine verbal condemnation and take concrete, collective measures to hold those responsible for violations of international law to account.
(Dr Aftab Alam is the Dean, Faculty of International Studies and teaches international law at Aligarh Muslim University. The views expressed are of the author and do not necessarily reflect the views of The News Analytics Herald.)
Key Takeaways
- Israel’s 2025 seizure of the Global Sumud Flotilla reignited debate on maritime law violations.
- UNCLOS guarantees freedom of navigation; Israel’s interception 70 miles offshore breached this right.
- The blockade, lacking UN approval, violates proportionality and humanitarian access obligations.
- Global famine warnings and ICJ rulings demand unimpeded aid to Gaza’s civilians.
- The case exposes a deeper crisis: power overriding law in international waters.
