Some of India's oil refiners resumed purchasing crude from Iran after the latter returned to the oil market last year, contributing to the collapse of wholesale crude oil prices across the globe.
According to data from ship-tracking services, in 2016 India imported some 473,000 barrels per day (bpd) from Iran to feed the former's expanding refining capacity, a significant rise from the 208,300 bpd in 2015.
In December 2016, imports from Iran were shown to have grown sharply, from about 181,200 bpd a year earlier, to a current 546,600 bpd.
"In most of 2016 there was a fight among Gulf producers to increase their market share and lifting of sanctions against Iran has intensified that fight," said Ehsan ul Haq, senior analyst at London-based consultancy KBC Energy Economics, cited by Reuters.
India remains the world's third-largest oil consumer. Overall, the country imported 4.3 million bpd of crude oil in 2016, up 7.4 percent from the previous year.
India's growing demand for oil is expected to continue, with energy information provider S&P Global Platts forecasting that New Delhi's consumption of oil will increase by 7 to 8 percent in 2017, outpacing Beijing.