Russia’s threat to seize Western merchant vessels in what Moscow calls a “symmetrical response” to action against its shadow fleet is more than another piece of aggressive rhetoric.
For Belgium, the issue is particularly relevant.
As one of Europe’s most important maritime and logistics hubs, Belgium sits at the intersection of shipping, sanctions enforcement, energy trade, insurance, customs controls and NATO security. Any attempt by Russia to turn commercial shipping into another arena of confrontation would therefore have consequences reaching well beyond the Baltic Sea.
The Kremlin’s latest message suggests that Moscow wants Western governments and commercial operators to believe that pressure on Russian-linked shipping could trigger retaliation against ordinary European vessels.
But the legal and military reality is far more complicated.
Moscow Is Trying to Create the Illusion of Equal Measures
The Russian position is built around the claim that detentions of vessels linked to its shadow fleet justify equivalent action against Western shipping.
That comparison is deeply misleading.
European authorities do not generally detain ships simply because they have commercial links with Russia.
Interventions usually involve specific legal concerns: unclear nationality, false registration, suspicious documentation, lack of valid insurance, sanctions violations, smuggling, environmental risks or other breaches of maritime rules.
A Russian naval vessel stopping and forcibly taking control of a properly registered Belgian, Dutch, French or British merchant ship on the high seas would be an entirely different action.
There is no automatic legal right of retaliation that would allow Moscow to treat ordinary European commercial shipping as a substitute target.
Why Shadow-Fleet Vessels Face Greater Legal Exposure
The weakness of the Russian shadow fleet lies partly in the methods used to keep it operating.
Vessels can change names, flags, ownership structures and management companies repeatedly. Their movements may be obscured, identification signals manipulated and registration arrangements shifted between jurisdictions.
These practices are designed to make sanctions enforcement more difficult.
They also make individual vessels legally vulnerable.
Under Article 92 of the UN Convention on the Law of the Sea, a ship should normally sail under the flag of one state.
Where nationality is unclear or a vessel appears to be using an invalid or false flag, authorities may have grounds to investigate its status.
That is very different from arbitrarily selecting a legitimate European merchant ship for retaliation.
Belgium Has Direct Experience With This Problem
Belgium is not an outside observer in the dispute.
The tanker Ethera, detained on 1 March while sailing under the flag of Guinea, remains one of the clearest examples of how European authorities are testing the limits of enforcement against suspicious shipping.
The vessel has remained under Belgian control pending a €10 million bail payment.
Its case illustrates both the willingness of European authorities to intervene and the legal caution surrounding such interventions.
Temporary detention does not automatically mean confiscation.
Investigations, documentation reviews, judicial oversight and financial guarantees all play a role.
That is precisely why the Kremlin’s description of European actions as “piracy” is difficult to sustain.
Europe’s Strategy Is Still Fragmented
The larger problem is that the European Union has not yet developed a fully unified method for dealing with Russia’s shadow fleet.
Different countries have taken different approaches.
Estonia detained Kiwala in April 2025 but later released it after its registration status was clarified.
France detained Grinch in January 2026 and released it after payment of a fine. The vessel later changed its name to Transformer and adopted the Russian flag.
The tanker Deyna was also detained by France and released after a financial penalty.
Tagor, detained under a Cameroon flag, was likewise freed approximately a month later.
These cases show a recurring pattern: intervention, investigation, legal procedure, then release.
That pattern is important because it demonstrates how far European governments remain from indiscriminate seizure.
Sanctions Do Not Create Unlimited Powers at Sea
The EU’s restrictions on Russian oil have a clear strategic purpose.
They are intended to reduce Russian energy revenues and limit the financial resources available to Moscow.
The EU, G7 and Australia introduced a price cap of $60 per barrel in December 2022. It was later reduced to $47.60 in July 2025.
But the mechanism does not amount to a global prohibition on Russian oil.
Third countries can still buy Russian crude.
What European countries can restrict is the involvement of companies under their own jurisdiction in transport, insurance, financing, brokerage and other maritime services connected with trade outside the permitted framework.
For Belgium, this distinction matters.
As a major centre for international logistics, port operations and European commerce, the country operates inside a sanctions system that is powerful but legally bounded.
Authorities still require a specific legal basis before physically detaining a ship.
The Port System Makes Belgium Strategically Important
Belgium’s geographical position gives the issue additional weight.
Major European trade routes pass through the North Sea, while Belgian ports connect maritime traffic with industrial, energy and logistics networks across the continent.
In any wider confrontation involving commercial shipping, ports would become crucial points for inspection, enforcement and monitoring.
That gives Belgium an important role in sanctions policy.
It also creates exposure.
Moscow does not need to attack Belgian ships directly to impose costs on the country.
Disrupted navigation, higher marine insurance premiums, tighter security requirements, delayed cargo movements and fears of sabotage could all affect European trade.
The Shadow Fleet Is No Longer Only an Oil-Sanctions Problem
Concern has also grown because some vessels associated with opaque shipping networks have been linked to incidents involving critical infrastructure.
The tanker Eagle S, sailing under the Cook Islands flag, damaged the Estlink 2 underwater cable between Finland and Estonia in December 2024.
Finnish authorities detained the vessel, but a court later found insufficient evidence to establish that the damage had been deliberate. It was eventually released.
At the end of 2025, the freighter Fitburg damaged another cable in the Gulf of Finland before also being released after investigative procedures.
Germany detained Scanlark in September 2025 over suspicions involving drones near a German naval vessel.
Investigators reportedly found a Russian-speaking crew and equipment that could potentially be used for surveillance.
The vessel was nevertheless released, later changed identity and continued operating.
These cases illustrate an increasingly uncomfortable reality for European governments: commercial shipping can become a platform not only for sanctions evasion but potentially for intelligence gathering, electronic interference and hybrid operations.
Underwater Infrastructure Is Particularly Vulnerable
For Belgium, this aspect should not be underestimated.
Europe depends heavily on subsea cables, energy infrastructure and communications systems crossing the North Sea and Baltic region.
Such infrastructure is difficult to protect continuously.
It is also vulnerable to incidents that can initially appear accidental.
That creates an ideal environment for hybrid operations.
A conventional military attack is easy to identify.
An anchor dragged across a cable, a navigation anomaly or a suspicious commercial vessel operating near critical infrastructure creates a much more complex attribution problem.
That ambiguity is strategically valuable to Moscow.
A Russian Warship Seizing a Belgian Merchant Vessel Would Be a Different Category of Incident
International maritime law gives Russia very limited grounds to stop a foreign merchant vessel on the high seas during peacetime.
Article 110 of the UN Convention on the Law of the Sea allows a warship to investigate a foreign vessel in specific circumstances, including suspicions of piracy, slave trading, unauthorised broadcasting, lack of nationality or use of a false flag.
Political retaliation is not one of those grounds.
If a Russian naval vessel seized a properly registered Belgian or other European merchant ship simply because a Russian-linked tanker had previously been detained in Europe, the action would have no comparable legal foundation.
Depending on the circumstances, it could constitute an internationally wrongful act or an unlawful use of force.
It would not technically be piracy because the vessel carrying out the seizure would be a state warship.
Responsibility would therefore fall directly on the Russian state.
Russia’s Naval Capacity Is More Limited Than Its Rhetoric Suggests
There is also a major operational problem for Moscow.
Russia would have to protect or escort hundreds of vessels linked to its shadow fleet across enormous distances if it wanted to transform its threat into a sustained maritime strategy.
Its navy is not positioned to do this effectively.
The Black Sea Fleet has been significantly constrained.
The Baltic Sea has become an overwhelmingly NATO-dominated maritime environment.
Russia’s Northern and Pacific fleets also carry strategic deterrence responsibilities that limit the forces available for prolonged commercial escort missions.
A systematic campaign against Western merchant shipping would therefore be expensive, difficult and extremely dangerous.
Direct Seizures Remain the Least Likely Scenario
A simplified model of Russian options suggests that an outright seizure of legitimate Western merchant vessels remains the least probable course.
The estimated probability of a serious direct maritime violation of this kind remains below 5%.
The reason is straightforward.
Such an incident would be difficult to disguise, impossible to dismiss as a misunderstanding and highly likely to provoke a coordinated Western response.
For Moscow, the political and military risks would be considerable.
Localised Detentions Are More Plausible
A more realistic option would be selective detention of Western ships inside areas controlled or claimed by Russia.
Moscow could invoke alleged environmental breaches, navigation violations or other regulatory claims.
Possible areas could include the Northern Sea Route or the Sea of Okhotsk.
Such cases could generate long legal and bureaucratic disputes while giving Russia the ability to claim that the action was administrative rather than retaliatory.
The probability of this type of scenario can be placed at roughly 25%.
Hybrid Maritime Pressure Is the Greatest Risk
The most probable Russian response is likely to remain below the threshold of open confrontation.
AIS interference.
GPS jamming.
Drone activity.
Suspicious damage to subsea infrastructure.
Use of proxy vessels.
Electronic warfare.
Potential covert mining.
Such scenarios offer Moscow several advantages.
They can disrupt maritime activity without requiring an openly acknowledged military operation.
They are difficult to attribute rapidly.
They can increase costs for commercial operators while leaving governments uncertain about how strongly to respond.
A modelling of these risks places hybrid maritime operations at up to 70%.
The Baltic Is the Immediate Flashpoint, but the North Sea Cannot Be Ignored
The Baltic remains the most obvious centre of confrontation.
Large volumes of Russian maritime oil exports leave Primorsk and Ust-Luga and then move through waters closely monitored by NATO states.
Russia has responded by deploying significant Northern Fleet assets, including the frigate Admiral Kasatonov and the destroyer Admiral Levchenko.
The deployment indicates that Moscow itself sees the Baltic as a zone where pressure on its shipping could become more serious.
But from Belgium’s perspective, the security problem does not stop at the Danish Straits.
The North Sea forms part of the same interconnected European maritime space.
Commercial vessels, energy routes, subsea communications, military traffic and port infrastructure all overlap.
An escalation that begins in the Baltic could quickly affect shipping conditions further west.
Belgium’s Real Challenge Is Not a Russian Boarding Party
The most dramatic scenario would be a Russian warship seizing a Belgian vessel.
It is also one of the least likely.
The more realistic challenge is a gradual increase in maritime insecurity.
A tanker behaving suspiciously near infrastructure.
Navigation systems becoming unreliable.
An unexplained cable failure.
A drone close to a military installation.
A vessel that changes its name, flag and owner shortly after being investigated.
Each incident can appear isolated.
Together, they form a pattern that is much harder for European governments to manage.
The Kremlin’s threat of “symmetrical retaliation” should therefore be viewed less as a credible promise of systematic naval seizures and more as part of a wider pressure campaign.
For Belgium, the central question is not whether Russian warships will begin hunting Belgian merchant vessels.
It is whether Europe can build a coherent maritime security strategy before shadow shipping, sanctions evasion and hybrid operations become permanently intertwined.
