The majority of India’s biggest refiners are buying Russian oil from non-sanctioned sellers and traders as widening discounts of Russia’s crudes to benchmarks are tempting the price-sensitive Indian importers, sources involved in the purchases told Bloomberg on Wednesday. Before the latest sanctions on Russian oil producers Rosneft and Lukoil, India bought from Russia around one-third of all the crude it imported, as it sought cheaper oil. Amid tense trade negotiations with the United States, India earlier this year was singled…