Indian Prime Minister Narendra Modi said Monday he was "deeply saddened and shocked by the tragic demise" of Iranian president Ebrahim Raisi after Iranian media reported he had died in a helicopter crash.
"My heartfelt condolences to his family and the people of Iran," Modi posted on X, formerly Twitter. "India stands with Iran in this time of sorrow."
India and Iran have had historically close relations, with the Islamic Republic for many years a key oil supplier to the South Asian giant, which is now the world's fifth-biggest economy, until US sanctions curtailed the trade.
New Delhi has had to balance its ties with Tehran with its links to Washington -- the United States and India are both members of the Quad security grouping -- and its warming relationship with Israel.
Iran and India signed a contract last week to develop and equip the long-stalled Chabahar port in an agreement that would give New Delhi 10 years' access to the facility, prompting Washington to warn that companies involved in the deal risked being sanctioned.
India's foreign minister S. Jaishankar also posted on X that he was "deeply shocked to hear of the passing away" of Raisi and his own counterpart Hossein Amir-Abdollahian.
"Our condolences to their families," he said. "We stand with the people of Iran at time of this tragedy."