Growing calls for the European Union to ban Russian oil imports may be overlooking a crucial flaw in its strategy to punish Moscow: India.

The South Asian nation is becoming a huge buyer of Russian oil, snapping up crude cargoes that are going unwanted by European importers. And with several European countries and oil majors self-sanctioning Russian purchases and starving themselves of fuel, India is already profiting from selling diesel onward to Europe.

If Europe adopts official sanctions on Russian crude and fuel, prices will likely surge, and India could profit even more from refining Russian oil to fuels it then sells to Europe for more money.