Kolkata Secretary of State Hillary Clinton is urging India to further curtail oil imports from Iran as part of a US-led campaign to pressure the Arabian Gulf state over its disputed nuclear programme. India is \"certainly working toward lowering their purchase of Iranian oil,\" Clinton told a town-hall style gathering of students and civic leaders in the eastern Indian city of Kolkata yesterday. \"We hope they will do even more,\" she said, adding that the US believes there are adequate supplies of crude in the international marketplace to enable it to do so. Clinton was to meet officials in New Delhi yesterday and today to discuss cooperation on issues that include stability in Afghanistan after the withdrawal of Nato troops and efforts to increase bilateral trade and investment, according to a State Department official who spoke on condition of anonymity. Her visit comes ahead of a June 28 US deadline to punish nations that don\'t significantly reduce oil imports from Iran. US sanctions have been an irritant in relations with New Delhi, which was the second-biggest buyer of Iranian oil last year. India imports about 70 per cent of its crude and has growing demands for an economy forecast to expand 7.3 per cent in the year through March 2013, making energy security a top concern for the government of Prime Minister Manmohan Singh. India, which says it has already reduced purchases from Iran to less than ten per cent of its crude imports, has criticised the imposition of unilateral sanctions by any one nation. Still, US and Indian officials say Singh\'s administration is quietly cooperating while seeking an exemption from the American penalties on financial transactions with Iran. The US law, along with a European Union oil embargo that takes effect July 1, are pillars of a campaign intended to squeeze Iran\'s main source of revenue and force the Arabian Gulf state to meet international demands over its nuclear programme, which the US, Europe and Israel say is a cover for developing an atomic weapons capability. Iran says it is for civilian energy and medical research. \"We do not believe Iran would\'ve come to the table if there were not sanctions and pressure,\" Clinton said yesterday. That\'s the \"reason why India, China, Japan, European countries who are the primary purchasers of Iranian oil are being asked to lower their purchases to pressure Iran.\" Representatives of the five permanent members of the UN Security Council — Britain, China, France, Russia and the US — plus Germany will meet with Iranian officials in Baghdad on May 23. The US has exempted ten EU nations and Japan from its upcoming sanctions, crediting them with significantly reducing imports of Iranian crude. Carlos Pascual, the US special envoy for international energy affairs in charge of negotiations with the 12 Iranian oil importing nations who have not yet been granted exemptions, will follow up on Clinton\'s visit with a mission to New Delhi later this month.