LONDON: French authorities Wednesday probed a vessel off western France alleged to be part of Russia's "shadow fleet" of oil tankers used to evade oil sanctions since its invasion of Ukraine.
The European Union has identified and blacklisted 444 vessels it says are part of the vast so-called Russian shadow or "ghost fleet", following an 18th tranche of sanctions announced in July.
The UK has sanctioned around 500 of these ships since February 2022.
The vessels, which fly flags of convenience and have opaque ownership, enable Moscow to keep exporting its crude oil for much-needed revenue despite curbs on exports.
What is a ghost fleet?
According to the UK government, such ships engage in illegal operations with the aim of circumventing sanctions, often evading safety and environmental regulations as well as insurance costs.
Such vessels existed before the war in Ukraine and are also used by Iran and Venezuela as a way of avoiding US sanctions, as well as by North Korea.
Since Russia's invasion of Ukraine in February 2022, the global shadow fleet "which previously mostly transported goods to and from Iran and Venezuela -- has exploded in size", according to the US think tank Atlantic Council.
It estimates that around 17 percent of all oil tankers belong to the global shadow fleet, which also comprises other merchant vessels.
Why is Russia using it?
An oil embargo, a price cap on Russian crude and a ban on providing services for shipping oil by sea have targeted profits crucial to Moscow, particularly for financing its war in Ukraine.
To circumvent the sanctions, Russia has had to reduce its dependence on Western maritime services and build up its own fleet by indirectly buying tankers, to which it offers its own insurance services.
In August 2025, 125 out of 400 vessels exporting Russian oil and oil products were shadow tankers, according to the Center for Research on Energy and Clean Air (CREA), a Helsinki-based think tank.
Of the ghost vessels, 38 were at least 20 years or older, it said.
What are the risks?
The Kyiv School of Economics (KSE) has warned of the "huge environmental risks for the EU" posed by the ageing ships.
The Atlantic Council estimated in early 2024 that ships over 20 years old would account for 11 percent of the global tanker fleet in 2025, compared to only three percent before the war in Ukraine.
The ships in the Russian ghost fleet do not have adequate protection and indemnity (P&I) insurance -- a must for commercial vessels to cover risks from war, collisions or environmental damage such as oil spills.
Up to 95 percent of the P&I insurance market is made up of insurers from the European Union and the UK, both of which have slapped several rounds of sanctions on Russia.