Iran’s senior leaders flooded the media with eve-of-poll warnings that abstentions in Friday’s parliamentary elections – either through indifference or as a protest – will only encourage Donald Trump to step up economic sanctions against Tehran.

The one-week period of officially sanctioned campaigning for a seat in the next five year parliament ended on Wednesday night, 24 hours before voting started amid the first serious outbreak of coronavirus in Iran.

Fifty-eight million Iranians are entitled to vote in what the Iranian government claims is the benchmark for democracy in west Asia, but which many in the west dismiss as an elaborate charade. On Thursday the US announced sanctions against five members of the guardian council, saying the body that vets all parliamentary candidates was guilty of electoral manipulation.

The elections are seen as a real chance for conservatives – known as “principalists” – to cement their grip on power by seizing control of one of the last of Iran’s political institutions outside their control.

Reformist politicians are divided: some favour abstention on the twin grounds that the elections have been rigged, through the mass disqualification of reformist candidates, and that the parliament is toothless, as legislation from the current Reformist-led parliament has been blocked by the council. “The last parliament tried to do something about political prisoners, and to go to visit the jails, and was just told to go away”, said one reformist.

But other reformists insist the stakes are too high to abandon the ground to hardliners.

Mostafa Kavakebian, a prominent Tehran reformist, wrapped up his campaign at Shahid Mo’atamedi, a sports complex in Khazaneh, a run-down working class neighbourhood in south Tehran, by claiming the future of the country as a semi-pluralist republic was at risk.

As he climbed into his car after a rally in front of 300 supporters, he was still complaining that too many reformists had been disqualified from standing by the guardian council.

Surrounded by reporters and jostling supporters, he said the reformists “ran out of time to challenge the disqualifications” and said the whole process – including the criteria by which candidates could be disqualified – needed overhaul. The outgoing parliament’s legislation to reduce the guardian council’s scope for interference had been blocked by the guardian council itself, he said.

In a speech, he warned: “If parliament becomes a political monopoly, the institutions parallel to parliament will be doubled in strength. The parliament will be neutralised and the republican aspect of the Islamic Republic system would be a show.”

He urged the Iranian government to stop dodging the blame for all the country’s problems: “We will not let people’s livelihoods get any worse. Our youth are unemployed and want jobs and housing. We should not hide these problems and simply put the responsibility of America, Israel and the Saudis. I know they are not powerful enough to do these things” .

He defended his long-term advocacy of engagement with the west, saying: “Our goal is to solve the issue of sanctions in order to solve the economic problems of the people. We have no desire to negotiate with the terrorist America that martyred [the commander of Iran’s Quds Force] Qassem Suleimani, but we believe we should have a interaction with the world.”

Profile Who was Qassem Suleimani? Show Qassem Suleimani, killed by a US drone strike in Baghdad, had become well known among Iranians and was sometimes discussed as a future president. Many considered Suleimani to have been the second most powerful person in Iran, behind supreme leader of Iran Ali Khamenei, but arguably ahead of President Hassan Rouhani. He was commander of the Quds Force, the elite, external wing of the Iran’s Islamic Revolutionary Guard Corps, which the Trump administration designated as a terror organisation in April last year. He was born in Rabor, a city in eastern Iran, and forced to travel to a neighbouring city at age 13 and work to pay his father’s debts to the government of the Shah. By the time the monarch fell in 1979, Suleimani was committed to the clerical rule of Ayatollah Ruhollah Khomeini, and joined the Revolutionary Guards, the paramilitary force established to prevent a coup against the newly declared Islamic Republic. Within two years, he was sent to the front to fight in the war against the invading Iraqi army. He quickly distinguished himself, especially for daring reconnaissance missions behind Iraqi lines, and the war also gave him his first contact with foreign militias of the kind he would wield to devastating effect in the decades to come. By the the time the Iraq government fell in 2003, Suleimani was the head of the Quds force and blamed for sponsoring the Shia militias who killed thousands of civilian Iraqis and coalition troops. As fighting raged on Iraq’s streets, Suleimani fought a shadow war with the US for leverage over the new Iraqi leadership. Once described by American commander David Petraeus as ‘a truly evil figure’, Suleimani was instrumental in crushing street protests in Iran in 2009. In recent months outbreaks of popular dissent in Lebanon, Iraq and Iran were again putting pressure on the crescent of influence he had spent the past two decades building. Violent crackdowns on the protests in Baghdad were blamed on militias under his influence.

Eighteen months before his death, Suleimani had issued Donald Trump a public warning, wagging his finger and dressed in olive fatigues. “You will start the war but we will end it.” Michael Safi Photograph: Mehdi Ghasemi/AFP

Many of those advocating abstention are close to despair and admit they have been over-optimistic about the change that can be achieved under the uncompromising supreme leader Ayatollah Ali Khamenei.

Yet some figures in government are nervous, fearing that the guardian council may have shot itself in the foot and depressed the turnout in urban areas by going so much further than normal in debarring so many prominent reformists.

As a result, patriotic calls to vote to defeat the west came from every layer of Iranian government – military, political and clerical.

Hesameddin Ashena, a senior adviser to the president, Hassan Rouhani, said that however angry people might feel, abstention “will only please Iran’s enemies and lead to increased sanctions, an increased probability of military invasion, larger budgets for hired anti-Iranian media, a decline in national resilience and reduced political bargaining power”.

Khamenei himself warned that “friends and foe are watching out for the election results”. He said the enemies wanted to see what had been the result of Trump’s policy of “maximum economic pressure”. He said it was not just an Iranian’s “national and revolutionary duty to vote, but a religious one”.

Even Mohammad Javad Zarif, the foreign minister, also said a big turnout would strengthen Iran diplomatically, although he said he would have preferred to have seen a wider choice of candidates.

A turnout well below 50% would probably unnerve the regime and reveal disenchantment with an apparently ineffective parliament.

In the 10 parliamentary elections since the 1979 revolution, turnout peaked at 71% in 2006. The lowest turnout was 51% in 2004, and the average is just over 62%.

Abbasali Kadkhodaei, the spokesman for the guardian council, predicted a turnout of more than 50%, although some say the turnout in reformist-minded cities such as the capital could be a derisory 30%

In the course of an hour-long press conference at a plush north Tehran hotel, Kadkhodaei was directly challenged about fixing the election. Question after question from foreign and domestic reporters focused on why he had disqualified so many reformists. None of the questions had been vetted in advance.

Impassive throughout and virtually hidden from view by a phalanx of microphones, he insisted the council “is not a political club, and simply follows the letter of the law as it had in previous elections”. He said it was up to the candidates to make public any reason they had been rejected.

Asked whether “a one-horse race tends to produce less interest in the outcome of the race”, he said this was not a relevant comparison, arguing there were “many political parties from which voters could choose”.

But rejected reformist candidates say their letters of rejection were explicitly political, citing issues such as their loyalty to the supreme leader, the nuclear deal or their attitude towards the hijab. “They are so arrogant they do not really hide what they are doing,” one activist said.