Key facts
- The number of shadow fleet ships sailing under false flags has been cut by more than half between October 2025 and June 2026.
- 107 shadow vessels have moved to the Russian flag registry since January 2025.
- The shadow fleet consists of aging, poorly insured tankers used by Russia to ship oil in violation of sanctions.
- European countries have increased enforcement against shadow fleet vessels.
- Open ship registries like Panama, Comoros, Barbados, and Palau have tightened oversight.
- The MV Sun oil tanker was boarded by an EU naval mission on Aug. 30, suspected of belonging to the shadow fleet.
European efforts to enforce sanctions against Russia's "shadow fleet" of oil tankers have significantly reduced the number of vessels operating under false flags, according to a report by the Center for Research on Energy and Clean Air (CREA). The crackdown has forced some of these vessels to register under the Russian flag, a move that CREA analysts suggest renders them immune to European interceptions.
The shadow fleet, comprising aging and poorly insured tankers, is used by Russia to export oil in defiance of international sanctions. Western governments also accuse Moscow of leveraging this fleet to support its hybrid warfare efforts.
European countries, including France, Sweden, Belgium, and the U.K., have become more aggressive in detaining suspected shadow fleet vessels entering their waters. Traditionally, these ships relied on cheap, lightly regulated open registries to conceal ownership. However, registries in countries like Panama, Comoros, Barbados, and Palau have tightened their oversight under Western pressure.
For instance, Barbados and Palau have removed all sanctioned 'shadow' vessels from their registries, while Panama has reduced its number of sanctioned 'shadow' vessels by nearly two-thirds since May 2025. This increased scrutiny has compelled many shadow fleet vessels to sail under false flags, making them legally stateless and providing European nations with grounds for detention.
The report noted that the number of shadow vessels flying false flags peaked at 101 in October 2025 and dropped to 45 by the end of June 2026. Concurrently, the Russian ship registry saw a 36% increase since early 2025, reaching 382 vessels by June 2026. Of these new Russian-flagged vessels, 87% were already under sanctions, and 56% had previously sailed under a false flag before adopting the Russian flag. However, the rate of vessels switching to the Russian registry has slowed since its peak in December 2025, with only three additions in June.