Approximately 61 million registered voters in Iran were called to the polls to elect the new president after the helicopter crash that killed former president Ebrahim Raisi at the end of May.

The snap election coincides with escalating regional tensions due to the current war between Israel and Iranian ally Hamas in Gaza and Hezbollah in Lebanon, as well as increased Western pressure on Iran over its nuclear programme.

Polls opened at 8am (04:30GMT) and will close at 6pm (14:30GMT).

A watchdog made up of six scholars and six jurists aligned with Khamenei vets candidates. It approved just six from an initial pool of 80. Two contenders subsequently dropped out.

Prominent among the remaining hardliners are Mohammad Bagher Ghalibaf, parliament speaker and former commander of the air force of the Islamic Revolutionary Guard Corps (IRGC), and Saeed Jalili, a former nuclear negotiator who served for four years in Khamenei’s office.

The sole comparative moderate, Masoud Pezeshkian, is faithful to Iran’s theocratic rule, but advocates some links with the West, economic reform, social liberalization and political pluralism.

All four candidates have promised to revive the flagging economy, beset by mismanagement, state corruption and sanctions reimposed since 2018, after the United States ditched Iran’s 2015 nuclear pact with six world powers.

If no candidate wins at least 50 percent plus one vote from all ballots cast, including blank votes, a run-off between the top two candidates is to be held on the first Friday after the election result is declared.

At just over 48 percent, the 2021 vote had the lowest turnout in any presidential election since 1979.