French President Emmanuel Macron has announced yet another highly provocative naval seizure of a Russian so-called shadow fleet vessel. 

"On Tuesday, the French navy boarded the oil tanker Deliver as it was passing off the coast of Sicily in breach of maritime law," Macron wrote in a post on X, revealing the prior interdiction that took place earlier in the week.

Reports say it flew a Cameroonian flag and was sailing from Russia's Baltic port of Primorsk, whereupon it was boarded by French forces over a falsified registration, according to the French maritime prefecture.

France's navy escorted then the tanker to an anchorage location, where it was subject to deeper inspections my maritime authorities.

It marks no less than the fifth such boarding of a 'shadow fleet' vessel suspected of transiting sanctioned Russian goods or energy off a European coastline since September.

"We will not allow the 'shadow fleet' to circumvent sanctions and finance Russia's war effort," Macron said.

The apparent legal justification France's navy has relied on for such actions is the practice of "flag-hopping" - which involves a crew repeatedly changing displayed flags, along with often invalid registrations to thwart international tracking monitors.

The last several seized tankers were also flying flags of African nations, and these interdictions have stretched back through last year. 

France's military released footage of the boarding of the 'Delivery'...

In some instances, Russia has been sending military escorts - which of course has seen French and European militaries hold off executing any action.

As a result of this latest intercept, it's likely Russia's navy will increase its military escorts, which has been more common in northern European waters, given the proximity to Russia.