Reformist candidate Masoud Pezeshkian wins Iran's presidential election. What it means.

A little-known heart surgeon who campaigned on limited, closer ties with the West and some reforms to strict moral codes for women prevailed in Iran's run-off presidential vote, the country's interior ministry said Saturday.

Cautious reformer Masoud Pezeshkian, 69, defeated Saeed Jalili, 58, an ultraconservative ideologue and former nuclear negotiator, according to Iran's state TV, citing the ministry. Pezeshkian's victory represents a blow to conservative political factions in Iran. In recent years, moderate voices have been sidelined.

However, Pezeshkian was expected to have little immediate impact on the Islamic Republic's policies because Iran's Supreme Leader Ayatollah Ali Khamenei, 85, tightly controls all top domestic and foreign matters of state. But Iran's new president will likely be closely involved in selecting Khamenei's successor and because he runs the government day-to-day, he can influence the overall tone of Iran's domestic and foreign policy.

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The vote comes amid tensions at home and abroad. Support for clerical rule in Iran has eroded at a time of growing public discontent over economic hardship and curbs on political and social freedoms. Meanwhile, the election coincides with escalating Middle East tensions due to Israel's war with Iranian allies Hamas in Gaza and Hezbollah in Lebanon. Iran is also facing increased Western pressure over its advancing nuclear program.

Iran's snap election for a successor to Ebrahim Raisi was called following his death in a helicopter crash in May. An earlier round with a field of four candidates failed to produce a clear winner.

The first round saw a record-low turnout of 40% because many Iranians had boycotted the vote as an act of protest. After voting finished at midnight Iran time, turnout stood at 50%, according to the interior ministry. The vote was called in Pezeshkian's favor after won 53% of more than 30 million votes counted. Jalili secured 44%.

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Pezeshkian is from Iran's Azeri minority ethnic group and he has emphasized supporting minority rights. While campaigning, Pezeshkian, a former health minister, criticized Iran's so-called morality police for cracking down too heavily on women protesters who have defied modesty dress codes. He also called for an end to Iran's "isolation" in the world and called for "constructive talks" with the West over Iran's moribund nuclear deal.

Ali Vaez, an expert on Iran at the International Crisis Group, a Belgium-headquartered think tank, said that Pezeshkian's win does not mean that the West is "going to be optimistic about the prospect of diplomatic engagement with Iran. The challenges are enormous, and the solutions to those challenges are not obvious."

He said that one of the main determining factors in whether there is a renewed push for diplomacy with the West, including putting new effort into resuming a 2015 nuclear accord between Iran and world powers, is not what happens in Iran's elections but rather what happens in the U.S. elections in November.

Former President Donald Trump withdrew the U.S. from the nuclear agreement.

"Even if there is another Biden administration resolving this is going to be extremely difficult," Vaez said, referring to the accord, known as the JCPOA. It was brokered under former President Barack Obama, when President Joe Biden was vice president. The agreement gave Iran sanctions relief in return for limiting its uranium-enrichment program, which Iran's critics say it is using to build a nuclear weapons program.

Iran has long maintained its nuclear program is for peaceful, civilian energy purposes only. Few believe that.

Vaez said that Iran's nuclear program is now "too advanced to be able to put back in a box. The sanctions are too complex to be easily rolled back. And world powers are now more divided."

He also said that in electing Pezeshkian, a crisis may have been averted. "With Jalili and Trump − those two presidencies together − Iran would have become the world's 10th nuclear weapons state."