Israel has boarded the Global Sumud flotilla, representing a further escalation of their response to flotillas seeking to deliver aid to Gaza. The boarding of the flotillas in international waters and the taking of people by force into Israeli territory violates multiple provisions of international law and the law of the sea. The UK’s lack of action, despite four of the boats in the Global Sumud Flotilla being British flagged (that is, by law, British territory) is concerning. This is a violation of the UK’s sovereignty under international law yet the UK is failing to act.
Interestingly, the issue of Israel boarding British flagged boats has received scant attention from the UK Parliament, despite proclamations around the need to protect British sovereignty. Indeed, the only mention of the flotillas in Parliament occurred in June 2025. Then, a motion was filed and supported by several MPs noting the illegal nature of the interception of the Madleen flotilla and raising concerns given that the Madleen was, also, British flagged. In response to a question posed by Labour MP Henry Tufnell that same month, which asked what the government was doing to secure aid for Gaza and whether they had discussed the Madleen with Israel (this question being posed prior to the Madleen’s interception), the government repliedstating that they had spoken to Israel and pressed them ‘to ensure that any action they took would resolve the situation… in line with international law.’ They did not, however, define what international law had to say about the situation. Neither did they note that any interception was, inherently, a violation of the law of the sea. Since then, there has been a resounding silence from the UK government in relation to the legal issues that arise from the interception of British flagged vessels in a flotilla.
In refusing to accept or apply international law Israel is acting as a rogue state. Israel refuses to accept the conflict as either an international or an internal armed conflict as both would have consequences for its actions; the former implying a recognition of Palestine as a state and the latter restricting its range of permissible responses. Both impose a range of rules around how Israel must treat the civilian population underinternational humanitarian law, but muddying the status of Palestine adds an element of distraction to the precise rules in question. On the specific issue of the “blockade” that Israel claims to be maintaining, the distinction matters. There are few examples of blockades being applied to non-international armed conflicts, making the use of blockade particularly difficult for Israel to justify. But the recognition of Palestine by an increasing number of states means that the better frame of reference is the law of international armed conflict. In that context, Israel might be legally able to search ships for contraband, but harassing vessels with drones, seizing them and their crews even if they are not carrying military materials, are all very different matters. Accusing the flotilla of being a “provocation” does not demonstrate any wrongdoing.
We have been here before, with tragic consequences. In 2010 a flotilla bound for Gaza in an effort to break the blockade was boarded by the Israeli military and ten people aboard the MV Mavi Mamara were killed. Multiple reports were launched into the events, with Israel’s official report, produced by the Turkel Commission, found that the blockade and the use of force to be legal. These findings were intensely controversial, not least in terms of how the principle of proportionality with regard to civilian harm was addressed. The Commission leant heavily on the findings by international agencies and charities that most Gazans were suffering “food insecurity” and not starvation, to justify the blockade as legal. Were the same resources to be relied upon in 2025, with starvation having been recognised in Gaza by a broad range of humanitarian organisations, there would be no such support for this conclusion.
The UK’s lack of action is part of a broader dynamic under which Israel refuses to accept or apply international law. The UK’s lack of response highlights that the UK’s formal recognition of Palestine as a state last month is merely performative. The UK Government’s position, after the seizure of the Madleen flotilla, that Israel must act ‘in line with international law’ has become nonsensical when, applying the rules of international armed conflict (as the UK must apply to this situation following its recognition of Palestine), the blockade cannot be lawful. The fact that several vessels in the flotilla were UK flagged means that these issues should not be treated by the UK Government as being too inconvenient for it to address.
Under the law of the sea, vessels are subject to the jurisdiction of their flag states. This is reflected in the affirmative duties of the flag state under UNCLOS Article 94 to exercise effectively its jurisdiction and control in administrative, technical and social matters over ships flying its flag. The stopping and boarding of British-flagged vessels by Israel in international waters, absent a valid legal basis, is a violation of the UK’s sovereign rights. The exceptions to this rule are narrow and do not apply here; the flotilla is not an act of piracy, nor were Israeli vessels engaged in “hot pursuit” from crimes committed in Israel’s territorial waters (12 nautical miles from shore) or contiguous zone (an additional 12 nautical miles). As other international law experts have pointed out, under UNCLOS, there is an argument to be made regarding Israel exercising control over the 12 nautical miles territorial sea off Gaza’s shores. However, this argument falls as soon as we start taking seriously the Palestinian people’s right to self-determination as expressed through Palestinian statehood. The international recognition of Palestine as a state should therefore also give rise to the recognition that the water off the coast of the Gaza Strip are Palestinian waters. In any event, Israel intercepted the Flotilla vessels between 70 to 80 nautical miles from shore, well beyond any state’s territorial waters.
Israel’s interception of vessels on the high seas, particularly those flying the flag of another state, is a clear violation of freedom of navigation on the high seas. While freedom of navigation is reflected under UNCLOS Article 87, it is also mostly considered customary international law meaning it applies to all states. The UK’s failure to assert its rights and condemn this violation or being mostly performative about it – as parliamentary discussions about the Madleen demonstrated – is also eroding customary international law. The persistence of a customary norm like freedom of navigation depends not only on state practice but also on its acceptance as law. When a flag state whose vessels are consistently subjected to unlawful denying of such right on the high seas responds with acquiescence or tacit compliance, it undermines the state’s own position with regard to international law. Such inaction can be interpreted as tolerating Israel’s actions, which if repeated by other states, even in such limited circumstances and context, begins to chip away at the normative foundation. Not only does this create a dangerous precedent that weakens UK sovereign rights upon vessels flying its flag, it also weakens freedom of navigation for all states, particularly those without significant diplomatic or naval power to enforce their own rights.
Romain Chuffart, Nansen Professor in Arctic Studies, University of Akureyri (Iceland)
Emily Jones, Senior NUAcT Fellow in Law, Newcastle University (UK)
Colin Murray, Professor of Law and Democracy, Newcastle University (UK)
Usual flummery about “international law”. Please start by recognising that law does not exist without a policeman. What we are talking about is international conventions; which sovereign states recognise or not as suits their purpose.
Academic attempts to place nation states in the dock for alleged breaches of “international law” are simply laughable.