France says it has seized an oil tanker in the Mediterranean suspected of being part of Russia's sanction-busting 'shadow fleet'.

French President Emmanuel Macron indicated that the vessel, named the Grinch, was subject to international sanctions and suspected of flying a false flag.

The French navy, along with allies such as the UK, boarded the vessel early on Thursday morning, situated between Spain and Morocco. A search confirmed the pre-existing concerns regarding the ship's flag legality.

Russia's embassy in Paris stated it had not been notified about the seizure.

Moscow's shadow fleet is known to utilize clandestine tankers to avoid Western sanctions on Russian oil exports, often employing older vessels with vague ownership details.

The Grinch was en route from the Arctic port of Murmansk in Russia when intercepted. It had been navigating under a Comoros flag, as per ship-tracking platforms.

Macron noted on X that France is devoted to upholding international law and enforcing sanctions, stating, The activities of the 'shadow fleet' contribute to financing the war of aggression against Ukraine. He added that the vessel had been diverted.

UK Defence Secretary John Healy confirmed that British naval forces provided tracking and monitoring support through the Straits of Gibraltar, emphasizing efforts to restrict funding that supports Putin's operations in Ukraine. The UK has already sanctioned 544 vessels linked to the Russian shadow fleet.

Ukrainian President Volodymyr Zelensky supported the seizure, asserting it embodies the resolve necessary to prevent Russian oil from funding military ventures. He demanded strict action against such vessels and proposed confiscating and reselling their oil cargo.

Zelensky also spoke at Davos, urging Europe to take more concrete measures for security, criticizing the tendency to delay action amid discussions on future policies.

Since the onset of the full-scale invasion of Ukraine in 2022, many Western nations have imposed strict sanctions on Russian energy sources. Earlier in January, British forces were involved in a similar operation targeting a Russian-flagged tanker in the Atlantic that was reportedly breaching sanctions by transporting oil for both Venezuela and Russia.

Russia condemned these actions, asserting that no state possesses the right to forcibly engage with ships properly registered under another state's jurisdiction. Last October, France seized another sanctioned vessel, the Boracay, though it was released shortly after.

The prevalence of shadow fleets has risen, with countries such as Venezuela, Iran, and Russia accused of employing such tactics to bypass sanctions. According to financial intelligence from S&P Global, about one in five oil tankers globally may be involved in smuggling efforts related to sanctioned regions.