• Critics have branded the elections to replace Raisi a 'sham' and called to boycott 

Iran is heading for a rare runoff election pitting a little-known 'reformist' against a hardline former nuclear negotiator following the lowest-ever poll turnout in the Islamic Republic's history.

Masoud Pezeshkian, the ostensibly 'moderate' option, bested the ultra-conservative candidate Saeed Jalili but fell short of the 50 per cent needed to secure majority. Iran's interior ministry has confirmed the second round of voting will take place on July 5.

Pezeshkian, 69, received 10.4 million votes while Jalili, 58, received 9.4 million of 24.5 million cast in Friday's election, though 61.5 million Iranians were eligible to vote on Friday. Low voter turnout is seen to reflect deepening public frustration following years of economic strife and political repression.

'Let's look at it as a protest in its own right: A very widespread choice to reject what's on offer - both the candidates and the system,' said Sanam Vakil, the director of Chatham House's Middle East and North Africa program. 

'That tells us a lot about public opinion and apathy, frustration. It sort of brings it all together.'

Tens of thousands of protestors meanwhile gathered across Europe on Saturday voicing antipathy towards the incumbent government and calls to boycott supreme leader Ali Khamenei's 'sham elections'.

With 60 per cent of voters casting no ballot at all in the election, support was dismally low for the remaining candidates as Iran sought to choose a replacement for President Ebrahim Raisi, killed in a helicopter accident last month.

Parliament speaker Mohammad Bagher Qalibaf received 3.3 million votes, while Shiite cleric Mostafa Pourmohammadi had over 206,000 votes.

Ultraconservative Qalibaf was the preferred candidate of Ayatollah Khamenei, the reigning head of state since 1989.

Pourmohammadi had threatened to split Pezeshkian's votes after appearing to step back from traditional conservative values to more moderate positions - but won just 0.8 per cent of the final vote.

But Pezeshkian is not widely viewed as the solution to Iran's woes, either. Critics say the more moderate option represents just another government-approved candidate.

With nobody able to gather a clear majority, Iran's top two candidates will advance to a run off in one week's time.

The only other runoff presidential election in Iran's history occured in 2005, when hard-liner Mahmoud Ahmadinejad bested former President Akbar Hashemi Rafsanjani.

As has been the case since the 1979 Islamic Revolution, women and those calling for radical change have been barred from running, while the vote itself will have no oversight from internationally recognized monitors.

There had also been calls for a boycott, including from imprisoned Nobel Peace Prize laureate Narges Mohammadi.

Mir Hossein Mousavi, one of the leaders of the 2009 Green Movement protests who remains under house arrest, also refused to vote along with his wife, his daughter said. 

Critics have branded the election a 'sham', and tens of thousands of protesters gathered on Saturday to voice opposition to the regime.

Maryam Rajavi, the President-elect of the National Council of Resistance of Iran, a political coalition calling for the regime's overthrow, told the Free Iran 2024 World Summit in Paris today the 'sham elections are the outcome of the impasse and the major failures that plague the regime'.

'The people of Iran have repeatedly and clearly declared, "Our vote is to overthrow the regime; there is no place for elections in this regime. It's time for revolution!"' she said.

'Direct monitoring and observation from the beginning to the end of the so-called voting... indicate that the boycott struck a sledgehammer blow against the regime, with 88 percent of Iranians abstaining from the fraudulent elections,' she continued.

'This overwhelming abstention represents the Iranian people’s decisive rejection of dictatorship and their clear vote for the regime’s overthrow, signaling the impending victory of a free Iran under a democratic republic.' 

'This election was intended to address Khamenei’s succession problem and secure the regime's continuity, but it has left the regime without a clear successor. 

'Darker days lie ahead for the clerical regime. The countdown to overthrow has begun,' she concluded.

Former Vice President Mike Pence, also speaking to an audience in Paris, told those resisting the regime at the Free Iran conference: 'I urge you from the bottom of my heart, to keep working, keep fighting, never stop believing in a free Iran, and never doubt that the freedom-loving American people are with you and support your dream of a secular, democratic Iranian Republic.

'When people ask why I chose to be here, the answer is simple. I want the world to know that because of all of you, the winds of change are blowing in Iran stronger than ever before.

'We gather at a momentous time in the wake of momentous events. I rejoice at the death of no man. But the death of President Ebrahim Raisi makes the future brighter, and the world is safer now that such an evil man has passed into history.'

Neither of Iran's two options heading into the July 5 runoff have done enough to convince critics they offer a viable alternative for Iran's future. 

In a documentary on the reformist candidate Pezeshkian aired by state TV, one woman said her generation was 'moving toward the same level' of animosity with the government that Pezeshkian's generation had in the 1979 revolution. 

'Pezeshkian has been a generally underwhelming candidate," the geopolitical consultancy Eurasia Group said in an analysis before Friday's vote. 

'Should he qualify for a runoff, his position would weaken as the conservative voting bloc unites behind a single candidate.'

Mrs Rajavi, speaking in Paris, warned: 'Reformists within this irreformable regime were this time used to increase turnout. 

'However, when asked, their candidate reiterated that his programs and policies are decided by Khamenei, and that deviating from them is a redline for him.'

Nonetheless, on Election Day, Pezeshkian offered comments on outreach to the West after voting seemingly aimed at drumming up turnout for his campaign - even after being targeted by a veiled warning from Supreme Leader Ayatollah Ali Khamenei. 

His opponent, Jalili, once described by CIA director Bill Burns as 'stupefyingly opaque' in negotiations, likely would have won outright had the three hard-liners not split Friday's vote. 

Jalili is known as the 'Living Martyr' after losing a leg in the 1980s Iran-Iraq war and is famous among Western diplomats for his haranguing lectures and hard-line stances.

Qalibaf, a former general in Iran's paramilitary Revolutionary Guard and head of Iran's police, had been thought to have a wider power base, despite being plagued by corruption allegations and his role in past violent crackdowns.

He quickly endorsed Jalili in conceding the result and criticized Pezeshkian for allying himself with President Hassan Rouhani and his former foreign minister, Mohammad Javad Zarif.

The two reached Iran's 2015 nuclear deal with world powers, which later collapsed after then-President Donald Trump unilaterally withdrew from the accord.

'The road is not over yet, and despite the fact that I respect Mr. Dr. Pezeshkian personally, ... I ask all the revolutionary forces and my supporters to help stop the wave that is causing an important part of our economic and political problems today,' Qalibaf said in a statement.

The winner of the Presidential Election will replace former President Raisi, who died aged 63 in a helicopter crash on May 19.

The crash also killed the country's foreign minister. 

Raisi was regarded with disdain by much of Iran's diaspora, associated with the mass executions in Iran conducted in 1988 and his role in the bloody crackdowns on dissent following protests over the death of Mahsa Amini, a young woman detained by police over allegedly improperly wearing the mandatory headscarf in 2022.

22-year-old Amini had recently been admitted to university and planned to become a lawyer when she was detained by police for improper wearing of a headscarf.

She fell into a coma after her arrest and died in suspicious circumstances in hospital in Tehran on 16 September 2022.

The Islamic Republic's officials told media that Amini suffered a heart attack while detained by 'morality police', denying reports she had been beaten.

Leaked medical scans and assertions of police brutality led observers to believe she had died at the hands of the police.

Iran witnessed its largest protests since at least 2009 in response to her death, amid a clash between a state tending towards stricter observation of inferred religious law and a more liberal Iranian community.

Iranian 'morality police' have since launched sporadic campaigns to verbally or violently arrest and 're-educate' women found in breach of regulations in response to changing dress codes and norms.