French customs have seized a yacht belonging to Rosneft boss Igor Sechin as it tried to leave the Mediterranean port of La Ciotat in a breach of EU sanctions on Russian oligarchs, Finance Minister Bruno Le Maire has said.
The move came as western states are implementing massive sanctions, including asset freezes, against Russia for invading its neighbour Ukraine.
A separate luxury yacht owned by Russian billionaire Alisher Usmanov worth nearly $600 million has also been seized, by German authorities, Forbes reported.
The 88-metre "Amore Vero" arrived in La Ciotat on 3 January and was due to stay there until 1 April for repairs, the finance ministry said in a statement, adding that the vessel was subject to the new sanctions.
Yesterday, customs officers noted the yacht was "taking steps to sail off urgently, without the repair works being over," the statement said, adding that the officers therefore decided to seize it.
The finance ministry said the yacht belongs to a company whose main shareholder is Mr Sechin, a close ally of Russian President Vladimir Putin. It did not name the company.
Monaco-based Imperial Yachts, which according to Refinitivdata is linked to Amore Vero, told Reuters the yacht was owned by a firm called Kazimo, which appointed them as managers of the boat in 2018.
"The individual you name is not connected with either Kazimon or the yacht," a representative for Imperial Yachts told Reuters, when asked about Mr Sechin.
"Kazimo's lawyers are in touch with French Douane in order to correct the record," they said.
The finance ministry did not immediately return a request for comment.
The superyacht was built by Oceanco in the Netherlands and delivered to its owner in 2013, according to yachtcharterfleet.com, which says its onboard features include a beauty salon and gym.
It sails under the flag of the Cayman islands, according to Eikon data.
"Thank you to the French customs officers who are enforcing the European Union's sanctions against those close to the Russian government", Finance Minister Bruno Le Maire said in a tweet.
French authorities have also seized a Russian-owned cargo vessel in the port of Lorient, Brittany.
The 150 metre Dilbar superyacht owned by Mr Usmanov, which boasts a 25-metre swimming pool, was taken in the northern port of Hamburg, the Forbes website reported.
Dilbar had been undergoing a refit in shipyards of Blohm +Voss, Forbes reported, adding that the German government had frozen the asset and employees working on the ship did not appear for work yesterday.
No one at Germany's General Customs Office was available to comment.
A spokesperson for Blohm + Voss declined to comment on the Dilbar, saying only that all orders and projects of the Luerssen Group and its subsidiaries were treated in accordance with the legal situation.
Forbes said representatives for Mr Usmanov did not immediately respond to a request for comment.
The EU imposed sanctions on the Russian tycoon and metals magnate and 25 other prominent people for Russia's invasion of Ukraine, according to a decision published in the EU's official journal.
Delivered in 2016, Dilbar is the largest motor yacht in the world by gross tonnage, according to the Luerssen website.
Among its recreational facilities is the largest-ever pool to have been installed on a yacht.
At least five superyachts owned by Russian billionaires were anchored or cruising on Wednesday in Maldives, an Indian Ocean island nation that does not have an extradition treaty with the United States, ship tracking data showed.