U.S. law places financial penalties on countries that don't take significant steps to cut back on Iranian crude oil imports. So far, 10 members of the European Union and Japan have received waivers for cutting back on their Iranian crude imports.
Clinton, during a briefing with reporters in New Delhi, said she felt India was "certainly" working on the issue.
Indian officials who spoke with the Bloomberg News agency on condition of anonymity said imports of Iranian oil could fall from 10 percent of the country's total oil imports to 7 percent by 2013.
"We hope that they will do even more, and we believe there is an adequate supply in the marketplace," she told reporters.
India had faced difficulties in purchasing Iranian crude oil because of financial restrictions placed on Iran's Central Bank.
Clinton said it is the responsibility of the international community to tighten the financial screws on Tehran in an effort to convince the Islamic republic to abandon its nuclear ambitions.
"So we appreciate what has been done, and of course, we want to keep the pressure on Iran, so whatever India or other countries can do will help us achieve that," she said.