Western nations allege Russia has been operating a "shadow fleet" to evade international sanctions imposed on its oil exports.

The UK Ministry of Defence says Russia has a fleet of more than 700 vessels, responsible for carrying 75% of the country's sanctioned oil.

This oil is a "critical lifeline for the Kremlin" in "sustaining Russia's illegal war", the MoD says.

Putin's comments come as the European Union intensifies pressure on Russia's shadow fleet.

In his remarks to Russian sailors, Putin singled out the EU, accusing member states of violating international maritime law and "attempting to restrict the movement of vessels belonging to our economic operators".

The BBC has asked the EU for comment.

Many Western countries imposed sanctions on Russian energy following Russia's full-scale invasion of Ukraine in 2022.

Moscow has been accused of dodging them by shipping oil on aged tankers often with obscure ownership or insurance.

To combat this tactic, in 2024 the EU began sanctioning individual shadow fleet vessels – "Putin's dark fleet", as the European Council, the bloc's top group of national leaders, put it.

More than 630 vessels are sanctioned as of mid-August 2026, meaning they are banned from EU ports.

Meanwhile, several individual European countries have been seizing or detaining Russian-linked vessels or have carried out boardings or detentions when sanctions violations are suspected.

Most recently, the Italian navy, in conjunction with other EU countries, boarded a tanker in the central Mediterranean suspected of not being entitled to fly the flag it claimed.

Although that inspection did not result in a seizure of the vessel, others have.

Since the start of the year, nine shadow fleet tankers suspected of circumventing sanctions have been seized around the EU.