India–Iran relations (; ) are the bilateral relationship between the Republic of India and the Islamic Republic of Iran. Independent India and Iran established diplomatic relations on 15 March 1950. However, ties between both ancient Persia and ancient India date back millennia. During much of the Cold War, relations between India and the erstwhile Imperial State of Iran suffered due to their differing political interests: India endorsed a non-aligned position but fostered strong links with the Soviet Union, while Iran was an open member of the Western Bloc and enjoyed close ties with the United States. While India did not welcome the 1979 Islamic Revolution, relations between the two states strengthened momentarily in its aftermath. However, Iran's continued support for Pakistan in the India–Pakistan conflict and India's close relations with Iraq during the Iran–Iraq War greatly strained bilateral ties. In the 1990s, both India and Iran supported the Northern Alliance against the Taliban in Afghanistan, the latter of which received overt Pakistani backing and ruled most of the country until the 2001 United States-led invasion. They continued to collaborate in supporting the broad-based anti-Taliban government, led by Ashraf Ghani and backed by the international community, until the Taliban captured Kabul in 2021 and re-established the Islamic Emirate of Afghanistan. India and Iran signed a defence cooperation agreement in December 2002.
From an economic perspective, Iran is the second-largest supplier of crude oil to India, supplying more than 425,000 barrels per day; consequently, India is one of the largest foreign investors in Iran's oil and gas industry. In 2011, the US$12 billion-worth annual oil trade between India and Iran was halted due to extensive economic sanctions against Iran, forcing the Indian oil ministry to pay off debt through a banking system via Turkey.
From a geopolitical perspective, despite the two countries having some common strategic interests, India and Iran differ significantly on key foreign policy issues. India has expressed strong opposition to Iran's nuclear program and while both nations continue to oppose the Taliban, India supported the presence of NATO-led forces in Afghanistan, unlike Iran.
According to a World Service Poll conducted by BBC at the end of 2005, 71 percent of Iranians viewed India's influence positively, with 21 percent viewing it negatively—the most favourable rating of India for any country in the world.
History
The Indian subcontinent and Iranian Plateau being adjacent geographical regions, Ancient India and Ancient Iran have had close relations dating back millennia. During the Middle Ages, there was fusion of medieval Persian culture in India, especially since the Delhi Sultanate till the period of Mughal Hindustan. In modern age, after the Partition of India in 1947, the newly independent India was no longer a neighboring country to the State of Iran, although the relations between both the nations still remained healthy.
Current relations
India and Iran have friendly relations in many areas, despite India not welcoming the 1979 Revolution. There are significant trade ties, particularly in crude oil imports into India and diesel exports to Iran. Iran frequently objected to Pakistan's attempts to draft anti-India resolutions at international organisations such as the OIC and the Human Rights Commission. India welcomed Iran's inclusion as an observer state in the SAARC regional organisation. A growing number of Iranian students are enrolled at universities in India, most notably in Pune and Bengaluru. The clerical government in Tehran sees itself as a leader of Shiites worldwide, including India. Indian Shiites enjoy state support such as a recognised national holiday for Muharram. Lucknow continues to be a major centre of Shiite culture and Persian study in the subcontinent.
In the 1990s, India and Iran supported the Northern Alliance in Afghanistan against the Taliban regime. They continue to collaborate in supporting the abroad-based anti-Taliban government led by Ashraf Ghani and backed by the United States. The two countries signed a defence cooperation agreement in December 2002.
In 2010, Iran's Supreme Leader, Ayatollah Ali Khamenei, appealed to Muslims worldwide to back the freedom struggle in Jammu and Kashmir. India in turn, summoned the acting Iranian ambassador in New Delhi to lodge a formal protest.