You might find this paper interesting, while I have not had time to read the whole thing yet its does seem full of useful information, even if I don't really agree with any of the UN findings
The Legality of the Israeli Naval Blockade of the Gaza Strip ...
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3.2 ISRAEL’S COMPLIANCE WITH THE LAW GOVERNING THE IMPOSITION OF THE NAVAL BLOCKADE
Israel maintains that the naval blockade was properly declared and notified.
(213) The naval blockade of the Gaza Strip began on 3 January 2009 and was announced on 6 January 2009.
(214)The Naval Blockade Notice stated: “All mariners are advised that as of 03 January 2009, 1700 UTC, Gaza maritime area is closed to all maritime trafic (sic) and is under blockade imposed by Israeli Navy until further notice”
(215) and also provided the geographical boundaries of the naval blockade by way of coordinates.
(216) It was published on international channels,
(217) and on the IDF, Shipping Authority and Ministry of Transport websites.
(218) Israel informed all vessels in the Mediterranean Sea about the naval blockade, transmitted the announcement twice daily to vessels located within 300 kilometres of the Israeli coast, and notified states which Israel knew had planned to send ships to the Gaza Strip.
(219) Israel asserts that the naval blockade has always been effective as no vessels have been permitted through,
(220) and that it has been enforced impartially and without discrimination against the vessels of all states.
(221) Israel also maintains that the naval blockade of the Gaza Strip has not prevented access to the ports and coasts of neutral states.
(222)
As regards Israel’s humanitarian obligations under the San Remo Manual, the Turkel Report concedes that it is possible that the naval blockade, combined with the Closure Policy, affects the civilian population of the Gaza Strip.
(223) However, it finds that there is no evidence that Israel is trying to starve the population of the Gaza Strip.
(224) It also accepts Israel’s position that “food insecurity” is not the same as “starvation”.
(225) It finds that the civilian population has not been denied objects for its survival and notes that Israel has permitted the passage of required items as well as humanitarian aid.
(226) The Turkel Report therefore concludes that there is no breach of Paragraph 102(a) of the San Remo Manual.
(227) As regards Paragraph 102(b) of the San Remo Manual and whether the damage to the civilian population is excessive in relation to the military advantage anticipated from the naval blockade, the Turkel Report accepts that it is difficult to assess the humanitarian repercussions of the naval blockade when it is examined separately to the Closure Policy that has been enforced since September 2007.
(228) It notes that as there was no Gazan port, there had been limited maritime trade via the Gaza Strip, and there are no records to refer to.
(229) It also notes that when humanitarian aid arrives by vessel, it is diverted to the Israeli port at Ashdod whereupon it is subjected to the Closure Policy.
(230) The Turkel Report also notes that Israeli caselaw supports the finding that Israel has complied with its obligations under Paragraphs 102(a) and 103 of the San Remo Manual.
(231) Finally, the Turkel Report refers to an International Committee of the Red Cross (hereinafter ICRC) report which suggests that medical supply stocks are low because of disagreement between Palestinian authorities, and not because of Israel’s non-compliance with Paragraph 104 of the San Remo Manual.
(232)
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