Moscow says US seizure of Russian tanker risks military escalation at sea
Russia’s foreign ministry accuses Washington of lowering the ‘threshold for use of force’
Russia’s foreign ministry warned the US seizure of a Russian-flagged tanker on Wednesday risked creating “further military and political tension in the Euro-Atlantic”, hinting that it risked provoking further violent incidents at sea.
The ministry said on Thursday that the US seizure of the Marinera was an “egregious violation of the fundamental principles and norms of international law” that “visibly lowers the threshold for the use of force” against maritime vessels.
The seizure will concern Russia, which is now likely to ship an increasing amount of its oil on sanctioned vessels such as the Marinera, that claim Russian nationality but had previously been operating without a flag state.
The US justified the interception by claiming the Marinera, added to the US sanctions list for links to the Iranian Revolutionary Guard in 2024, was “responsible for transporting sanctioned oil from Venezuela and Iran”.
In previous statements, the US had also referred to the statelessness of the ship. The Marinera was originally intercepted near the Caribbean in late December, when the empty vessel was sailing west to pick up oil from Venezuela.
According to the International Maritime Organization, at this time, it was falsely claiming to be registered as a Guyanese ship. Under the UN Convention on the Law of the Sea, the vessel would have been legally boardable by a warship as the ship was “without nationality”.
After refusing to be boarded, the ship sailed north-west across the Atlantic, and was pursued by the US Coast Guard ship, the USCGC Munro. It was finally seized about 325km south of Iceland.
During its journey across the sea, however, the vessel was sold to a Russian company based in Ryazan and reflagged as a Russian ship, meaning the authorities in Moscow regard it as operating under their jurisdiction and oversight.
FT analysis has identified 11 other similarly stateless ships that have recently moved Russian oil and were granted a Russian flag since November. These ships were all recent members of the so-called ghost fleet, the group of tankers whose unknown ownership complicates sanctions enforcement action. In each case, the vessel had moved Russian oil since January 2025.
A further five stateless ships in the ghost fleet were given Russian nationality earlier in 2025.
“Inspired by the dangerous and irresponsible precedent set by Washington, certain other countries and structures may consider themselves in the right to use these methods,” the Russian ministry said.
The ministry said the US sanctions cited as justification for the detention were “illegitimate” and called US claims the seizure was part of attempts to gain control over Venezuelan oil exports “extremely cynical”.
It said Russia had repeatedly sent the US “reliable information” that the Marinera changed its jurisdiction to Russia late last month and denied US claims it had sailed under a “false flag”.
John Healey, the UK defence secretary, called the legality of the switch into question on Wednesday, saying it had “tried to adopt the Russian flag”. Referring to it by its pre-switch name, the Bella 1, he said it was “a sanctioned, stateless vessel”.