Britain defended its detention of the Smyrtos in the English Channel after Russian President Vladimir Putin warned that Moscow would "respond in kind" to further seizures of vessels tied to Russia's shadow fleet (ships used to hide sanctioned oil trade). Royal Marines Commandos intercepted and boarded the tanker in June in what the UK described as a first-of-its-kind operation, and captain Ajay Pant has been charged with breaching Russian sanctions by allegedly directly or indirectly supplying or delivering prohibited Russian oil. The UK Ministry of Defence says Russia's shadow fleet numbers more than 700 vessels and carries 75% of the country's sanctioned oil, while the European Union continues tightening enforcement, with more than 630 vessels sanctioned as of mid-August 2026 and nine seized around the bloc since the start of the year.