Russian authorities have accused the United States of violating the United Nations Convention on the Law of the Sea following the interception of tankers belonging to the so-called “shadow fleet.” Washington, for its part, insists on the legality of its actions, claiming that the vessels themselves were violating international norms. Despite the harsh rhetoric, Moscow does not appear ready to take retaliatory measures that could lead to military escalation.
What happened
On January 7, U.S. armed forces intercepted two tankers involved in transporting “sanctioned” oil. One of them, Bella 1, had been under surveillance by U.S. Navy ships for several weeks. On December 30, the tanker announced a change of flag, switching from the Guyanese flag to the Russian one, and was renamed Marinera. Moscow then demanded that Washington stop the pursuit and dispatched warships and a submarine to meet the vessel. These actions, however, only delayed the operation: a U.S. commando unit eventually boarded the tanker. After the interception, Russia’s Ministry of Transport, followed by the Ministry of Foreign Affairs, accused the United States of violating international maritime law.
U.S. position
The American side refers to Article 92 of the United Nations Convention on the Law of the Sea, which prohibits changing a vessel’s flag at sea except in cases of a genuine transfer of ownership or a change in registration. As international maritime law expert Pierre Tevenin explains, when a ship illegally changes its flag while at sea, it effectively loses its nationality. In such a case, it no longer falls under the exclusive jurisdiction of the flag state, meaning any warship may inspect and detain it. This is precisely the logic invoked by the United States, which argues that Bella 1 lost its legal protection, making the operation lawful. Estonian and French authorities used similar reasoning when intercepting Russian “shadow fleet” tankers in 2025.
Where the United States violates international law
The situation is different with regard to the second vessel, Sofia, which, according to CBS, sails under the Cameroonian flag. The United States accused it of violating its own embargo against Venezuela. From the standpoint of international law, this argument appears weak. The embargo was not authorized by the UN Security Council and therefore constitutes an illegitimate instrument of pressure on a sovereign state, contradicting Article 2(7) of the UN Charter. Moreover, it infringes on freedom of navigation and the right of innocent passage in territorial waters, the exclusive economic zone, and on the high seas. Finally, the interception of Sofia violates Cameroon’s jurisdiction, since only that state has the right to arrest a vessel flying its flag. Without its consent, the United States could intervene only in cases of piracy, drug trafficking, human trafficking, or illegal broadcasting, none of which were established in this case.
Russia’s position
Russia’s position is based on the same Article 92 of the Convention, but emphasizes its exceptions. Moscow claims that the flag change of Bella 1 was legal because it was accompanied by a genuine transfer of ownership and re-registration. Journalists from the Financial Times revealed that in December the tanker came under the control of the Russian company Bourevestmarine. In addition, the vessel was entered into the Russian maritime register, and in the database of the International Maritime Organization the change of flag was recorded without any indication of fictitious status. If these details are confirmed, Russia will have strong arguments before international bodies.
Who is right and what comes next
There is, however, no clear answer as to who is right. Changing a flag during an active pursuit constitutes a precedent in international maritime law. In the event of legal proceedings, the United States will seek to prove that the transaction was fictitious, while Russia will defend its legality. The legal assessment of the entire operation will depend on this. At the same time, as Pierre Tevenin notes, even assuming the flag change was illegal, Russia has no grounds for a military response. The expert considers an escalation of the conflict to an armed confrontation extremely unlikely.
