https://theconversation.com/there-are-clear-laws-on-enforcing-blockades-israels-interception-of-the-madleen-raises-serious-questions-258562
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Legal conditions for naval blockades
Naval blockades are not automatically illegal. Under the San Remo Manual on International Law Applicable to Armed Conflicts at Sea (1994), a blockade may be used in wartime, but only if five legal conditions are met:
- it must be formally declared and publicly notified
- it must be effectively enforced in practice
- it must be applied impartially to all ships
- it must not block access to neutral ports or coastlines
- it must not stop the delivery of humanitarian aid to civilians.
If even one of these conditions is not met, the blockade may be considered illegal under customary international humanitarian law.
The fifth condition is especially important here. According to a comprehensive study of international humanitarian law conducted by the International Committee of the Red Cross, the parties to a conflict must allow the rapid and unimpeded delivery of humanitarian relief to civilians in need.
A blockade that prevents this could be in breach of international law.
Israel and Egypt have imposed a blockade of varying degrees on Gaza since 2007 when Hamas came to power. Israeli Defence Minister Israel Katz claims the purpose of the blockade is to “prevent the transfer of weapons to Hamas”. Critics say it amounts to collective punishment.
The Madleen was operating in compliance with three binding International Court of Justice orders (from January 2024, March 2024 and May 2024) requiring unimpeded humanitarian access to Gaza.
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A fact-finding mission established by the UN Human Rights Council found that Israel violated a number of international laws and that its blockade was “inflicting disproportionate damage upon the civilian population”.
This is not just a political or moral issue – it’s a legal one. International law lays out clear rules for when and how a country can enforce blockades, intercept vessels and treat civilians.
Based on these rules, serious legal questions remain about Israel’s handling of the Madleen and its passengers.
