The sole reformist in Iran's presidential election, Masoud Pezeshkian, will face the ultraconservative Saeed Jalili in a runoff, authorities said on Saturday, following a vote marred by historically low turnout.

Pezeshkian secured 42.4% of the vote, while Jalili, a former nuclear negotiator, came second with 38.6%, according to figures from Iran's elections authority.

Conservative parliament speaker Mohammad Bagher Ghalibaf was next with 13.8%, while the only other candidate, conservative cleric Mostafa Pourmohammadi, got less than 1%.