How Qualified Neutrality Impacts the Law of Contraband

by | Jul 11, 2023


It is often thought that the outcome of the Russia-Ukraine conflict may depend heavily on the amount and type of military equipment that both parties are able to bring to the battlefield. Depriving the enemy State of material it needs to sustain its warfighting capabilities, is, therefore, of critical importance.

Current views on neutrality form the basis for States to support Ukraine’s warfighting capabilities through the delivery of military equipment, training, and financial support. From a Russian perspective, this support arguably calls for economic warfare strategies to supplement its military warfighting strategy.

Until now, although it has taken measures to gain sea control in the Sea of Azov and the northern Black Sea, Russia seems not to have exercised its rights under the law of contraband against the influx of arms and arms-related materiel via the sea. This post argues that, apart from political and operational reasons that may underlie this choice, the qualified neutrality position has made the application of the law of contraband more complex or even void in the context of governmental arms and arms-related materiel shipments to Ukraine.

The Law of Contraband

Contraband are goods susceptible to use in armed conflict. The law of contraband is applied against neutral merchant vessels during an international armed conflict. With exceptions, such as the Paris Declaration of 1856 and the Hague Convention (XI) relative to certain Restrictions with regard to the Exercise of the Right of Capture in Naval War of 1907, most rules on the law of contraband are customary international law. The London Declaration of 1909 contains detailed provisions regulating contraband, but it never entered into force. The key requirements for belligerent warships to exercise counter-contraband operations against neutral merchant vessels based on the law of contraband are: 1) that the cargo must be considered contraband; and 2) that the goods must ultimately be bound for an enemy destination.

Character of Goods

Which goods can be regarded as contraband has always been a matter of controversy. Whereas arms and ammunition or other typical military materiel are obvious contraband, categorization becomes more difficult with dual-use goods. For instance, raw materials, foodstuffs, or anything else that supports the warfighting effort can be difficult to classify. In the past, States also distinguished between absolute contraband, which are war materials that can be captured if destined for enemy controlled territory, and conditional contraband, which are basically dual-use goods that can be captured when destined for enemy controlled territory and of which it can be sufficiently proved that they will be used for war-like purposes.

Enemy Destination: Continuous Voyage

Along with its character, contraband must be destined for territory under the control of the enemy. Only contraband that satisfies this criterion can be seized. When the doctrine of continuous voyage is applied in contraband law, contraband goods can also be seized when they will first be delivered at a port that is not under control of the enemy. But it must be established that these goods will ultimately be transported to enemy territory. For example, in present circumstances, contraband on board a neutral merchant vessel that is bound for the port of Rotterdam, which will then be transported over land to Ukraine, could be seized at sea. Applying this doctrine, therefore, entails a considerable expansion to the geographical area of application of contraband law.

Contraband Lists

Whether belligerent States must publish contraband lists to make use of their belligerent rights is somewhat unsettled. The London Declaration set up a system of lists that clarifies what is considered contraband withoutgiving any notice to neutral States if war breaks out (art. 22-44). But this system never came into effect. The San Remo Manual clearly states that belligerents must have published contraband lists in order to exercise their right to capture contraband (§ 149). Some States follow this view; others have no position. The United States takes the view that, “Though there has been no conflict of similar scale and magnitude since World War II, post-World War II practice indicates, to the extent, international law may continue to require publication of contraband lists, the requirement may be satisfied by a listing of exempt goods” (U.S. Commander’s Handbook on the Law of Naval Operations, para. 7.4.1). Although this view seems logical from an operational standpoint—because it gives a State maximum flexibility to apply the law of contraband at sea—it also impacts clarity on which goods are considered contraband. Furthermore, this approach should also be accepted in a reciprocal manner.

Assuming Russia has not published any lists, as one report indicates, the question therefore arises whether this would legally bar Russian naval forces from exercising belligerent rights to seize contraband. As stated, a generally accepted answer to this seems somewhat unsettled, but it may not be an issue if the belligerent State and the neutral State take the same view. It is unfortunately unknown what the Russian view is regarding publication of contraband lists.

Neutrality and Immunities

Arms and arms-related materiel transported by neutral States to Ukraine (or Russia) would arguably qualify as contraband. With the current grain deal in place (discussed here by Pete Pedrozo) that implements a strict inspection regime, other Ukrainian ports under Russian occupation and closed Turkish Straits, it is very unlikely that vessels with contraband would be directly bound for Ukraine to deliver arms. The doctrine of continuous voyage, however, allows that vessels can also be seized elsewhere at sea when the vessel is bound for other ports and it can be proven that arms shipments are ultimately destined for Ukraine. Leaving aside political and operational challenges, this scenario seems to open opportunities for Russia. Yet it is here that the current view on the law of neutrality becomes interesting in terms of the law of contraband.

First, Article 6 of the Hague Convention XIII concerning the Rights and Duties of Neutral Powers in Naval War (1907) explicitly forbids a neutral power to supply, directly or indirectly, war ships, ammunition, or war material of any kind. Apart from the question whether this provision is considered customary or only applies between the Parties to the treaty, in the case of the Russia-Ukraine conflict and in light of the current interpretation of neutrality, this provision appears to have become moot. Accepting the qualified neutrality position, would, as Professor Heintschel von Heinegg states, mean that “the many States supplying Ukraine with military equipment—whether defensive or offensive is irrelevant—are not acting contrary to the law of neutrality, nor are they otherwise committing internationally wrongful acts or aiding and assisting such acts.” Either one could continue this line of argument and conclude that arms shipments undertaken in this context should then also not be considered as contraband because it is not prohibited to support a belligerent State under such circumstances. Or one could take a position that it may perhaps not breach a State’s neutrality, but the belligerent Parties can still continue trying to stop shipments from reaching their opponent.

Second, even if Russia does consider the arms shipments as contraband, the issue of immunity of vessels complicates the application of the belligerent right of visit. As mentioned, the law of contraband applies to neutral merchant vessels. It cannot be exercised against State vessels that enjoy immunity, such as warships, auxiliary vessels, and State vessels performing non-commercial service. Questions, however, could be raised whether the belligerent right of visit and search is also excluded from applying to neutral merchant vessels chartered by a State and performing non-commercial services.

The law of naval warfare and the San Remo Manual are, quite logically, silent on the matter as the regime is conceptually based on the idea that States should not engage in such activities. The United States considers that “Other neutral vessels engaged in government non-commercial service may not be subjected to visit and search.” (U.S. Commanders Handbook, para. 7.6). This is most probably (and logically) drawn from the acta iure imperii principle (and coming from the idea that public activities of one State cannot be subjected to powers of another State), which for the maritime dimension in peacetime circumstances translates to immunity for merchant vessels in government non-commercial service.

The recent Newport Manual on the Law of Naval Warfare considers that such vessels are entitled to sovereign immunity, but does not go on to explicitly state that they are excluded from the belligerent right of visit and search. If one would follow the U.S. position of immunity to the belligerent right of visit and search during international armed conflict, and given the current view on neutrality, this would mean—from a belligerents’ perspective—that there is neither a possibility to stop contraband at sea, nor a possibility for the belligerent Party to claim at State level that neutrality has been breached. Although the law of contraband could still be exercised against neutral merchant vessels carrying contraband that are not chartered by a State, it minimizes possibilities for belligerent States to stop governmental arms shipments.

Questions for States

Looking at the Ukraine-Russia conflict from a law of contraband perspective raises interesting “what if” questions, in view of the current neutrality positions, that States should be asking themselves if they also transport arms to the conflict area via the sea. What is, for instance, their view on the publication of contraband lists, the application of the doctrine of continuous voyage to (absolute and conditional) contraband and would States allow merchant vessels chartered by the government to undergo visit and search by a belligerent Party, or even be diverted? Although the law of contraband does not appear to offer a fully developed and applied legal system yet, this conflict has shown that provisions of the law of war that were thought to have a dormant existence might awaken at an instant.


Commander Martin Fink is a legal advisor in the Royal Netherlands Navy and research fellow at the Royal Netherland Defence Academy. He currently holds the position of Head of Legal Affairs of the Royal Marechaussee.


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