The company has a deal to buy 180,000 barrels per day (bpd) Iranian oil this fiscal year, Reuters reported.
He said India's overall oil imports from Iran could exceed last year's level.
The official, who did not want to be identified, said Indian refiners are prepared to pay for Iran oil imports entirely in rupees through state-owned UCO Bank.
During Iranian President Hassan Rouhani's visit to New Delhi in February this year, India had agreed to raise Iranian crude oil import to around 25 million tons during the current fiscal year in comparison to 18.5 million tons in 2017-18.
In 2016-17, India had imported 25.5 million tons of crude oil from Iran. Government data shows that New Delhi has already imported 15.05 million tons of crude from Iran between April and September 2018.
In value terms, the crude import bill from Iran between April and September 2018 more than doubled to $7.74 billion from $3.84 billion in the corresponding period in the last fiscal year.