Indian refiners boosted U.S. crude oil purchases this month, drawn by competitive prices, trade sources said, a move that could help narrow the country's trade deficit with the United States amid tensions between the two nations.

The country's top refiner, Indian Oil Corp, has bought 5 million barrels of U.S. West Texas Intermediate crude for delivery in October and November via a tender, trade sources said.

This came after another state refiner Bharat Petroleum Corp purchased 2 million barrels of U.S. WTI crude while private refiner Reliance Industries has bought 2 million barrels of WTI crude from Vitol, other sources said.

Indian refiners, along with others in Asia, stepped up purchases after the arbitrage window for U.S. crude to Asia opened. India is also under pressure to buy more U.S. oil after the United States doubled its tariffs on Indian imports to 50%, citing New Delhi's buying of Russian oil.

European traders Gunvor and Equinor sold 2 million barrels each, while Mercuria sold 1 million barrels to IOC, the sources said.

Meanwhile, BPCL has also made its first purchase of Nigerian Utapate oil as it expands its crude diet to include new grades, they added.