Russia has deployed a submarine and other naval assets to escort a derelict oil tanker in the North Atlantic, escalating what began as a sanctions enforcement operation into a tense geopolitical standoff with the United States, according to the Wall Street Journal, citing US officials.

The vessel, now sailing as Marinera, is being shadowed by the US Coast Guard weeks after departing Venezuelan waters. Though empty and deteriorating, the tanker’s journey has drawn intense scrutiny as part of Washington’s effort to curb a global network transporting illicit oil linked to Russia and other sanctioned states.

Formerly named Bella 1, the tanker had attempted for over two weeks to evade a US-led blockade targeting sanctioned oil shipments. In December 2025, the crew resisted a US boarding attempt, painted a Russian flag on the hull, renamed the vessel Marinera, and re-registered it in Russia—moves that complicate legal action under international maritime law.

According to US officials, Russia has formally requested Washington halt its pursuit, while Moscow’s Foreign Ministry said it is monitoring the situation “with concern.” The US Southern Command affirmed readiness to act against sanctioned vessels in the region.

AIS tracking shows the tanker now sailing roughly 300 miles south of Iceland, heading toward the North Sea. Russia’s state media RT released footage claiming the ship is being unfairly pursued despite its “civilian status.”

The legal situation remains murky. While the US initially considered Bella 1 stateless and subject to seizure for allegedly transporting black-market Iranian oil, its registration in Russia now grants it legal protection under international law. Experts warn any US boarding attempt could provoke retaliation from Russia or its allies, including Iran.

The standoff occurs amid broader US-Russia tensions over Ukraine. Analysts caution that the tanker dispute may complicate diplomatic negotiations, with Moscow’s support for the “dark fleet”—a network of over 1,000 opaque, often untracked tankers—highlighting the challenge of enforcing Western sanctions. Russia’s decision to allow Marinera’s registration without standard inspections is seen as an unusual move reflecting concern over US seizure of vessels accused of transporting illicit Russian oil, a trade that continues to underpin parts of the Russian economy.