The world does not have a system to trace Russian oil as it is refined overseas, Shell's boss said on Thursday, meaning Western government's efforts to ban its use can only reach so far, according to Reuters.
While Europe considers joining the United States and Britain in banning imports of crude oil and refined products of Russian origins, sanctions do not cover imports of fuels such as diesel and jet fuel from refineries in other countries that might be produced from Russian crude.
Shell, the world's largest oil trader, no longer trades any Russian oil and plans to unwind most of its long-term Russian purchase contracts by the end of the year.
"We do not have systems in the world that trace back whether that particular molecule originated from a geological formation in Russia.... that doesn't exist," Shell Chief Executive Ben van Beurden told reporters after the British company reported a record profit in the first quarter.
Russia last year supplied over a quarter of Europe's crude oil and refined products.
Current sanctions do not take into account where a Russian crude is refined and treated, he said.
"So therefore, diesel coming out of a Indian refinery that was fed with Russian crude is considered to be Indian diesel."