Nayara Energy, an Indian refiner part-owned by Russia's Rosneft and newly sanctioned by the European Union, has revised payment terms to sell a spot naphtha cargo in a tender issued on Monday, according to a document seen by Reuters.

India's petroleum trade with the European Union is entering a precarious phase. With the EU contemplating restrictions on Russian crude that has been refined outside its borders, India's robust $15 billion petroleum export market is at risk.