Put into a difficult situation by U.S. pressure, India said it would buy crude oil from other major oil producing countries to protect its interests.
Washington has renewed sanctions on Iran in an attempt to eliminate all of its oil revenue, which it says funds destabilizing activity throughout the Middle East and beyond.
In November, the U.S. granted a six-month waiver to India and seven other countries to continue importing oil from Iran. The waiver ended early this month.
Indo-Iran ties have expanded in various fields in recent years.
During his visit to India last year, Iranian President Hassan Rouhani said Iran and India were prepared for joint ventures in gas and petroleum. He sought India's investment in these areas, as well as in industry and mining.
India is helping Iran develop Chabahar Port on the Gulf of Oman for trade with Afghanistan and Central Asia, bypassing Pakistan, which has refused to provide New Delhi access through a land route.
India committed up to $500 million for the development of Chabahar along with associated roads and rail lines. This project is unlikely to be hit by the U.S. sanctions on Iran.