The sole reformist candidate in Iran’s presidential election has vowed to try to resolve the stand-off with world powers over the nuclear deal “at first chance” if he is elected.

In an interview with the Financial Times, Abdolnaser Hemmati, a former central bank governor who is battling hardline rivals in Friday’s vote, said if he won his priorities would be the revival of the 2015 nuclear accord, an agreement to lift US sanctions and attracting foreign investment.

“If the US returns to its commitments under the JCPOA [the nuclear accord] and Iran can verify that they have lifted the sanctions . . . it would be an important step toward trust-building between Iran and the US,” he said.

Polls suggest Hemmati is running a distant second to his main hardline rival Ebrahim Raisi and the odds appear stacked against his chances of pulling off a shock victory. But the 64-year-old said he had already asked Mohammad Javad Zarif, Iran’s top diplomat and one of the architects of the nuclear deal, to be in his government.

He added that if sanctions were lifted and conditions improved, a meeting with US president Joe Biden would “not be impossible”. “In general, I do not reject [the possibility of talks with the US] but it will depend on the US’s behaviour and deeds,” he said. “My priority is to lift the sanctions. This is very important,” he added.

Hemmati’s comments underscore what is at stake in the election and highlight the differences between the reformist and his hardline rivals after four years of hostilities between Tehran and the Trump administration.

Raisi, the frontrunner, has suggested that if he wins he will support ongoing negotiations between Tehran and the nuclear deal’s remaining signatories — the UK, France, Germany, Russia and China — that are intended to broker an agreement that would lead to the US rejoining the accord and the removal of sanctions.

But analysts say Raisi, head of the judiciary, is expected to adopt a far more conservative approach and not prioritise relations with western states. Raisi has said his focus will be on bolstering domestic industrial production. This puts him more in line with the stance articulated by Ayatollah Ali Khamenei, Iran’s supreme leader, who many Iranians suspect favours Raisi. While Khamenei has the final say over all crucial foreign and security policies, the president can influence the direction Iran takes.

Outgoing president Hassan Rouhani signed the nuclear deal in 2015 under which Tehran agreed to strict limits on its nuclear activities in return for the US removing sanctions. But the accord collapsed after Donald Trump unilaterally withdrew the US from the deal in 2018 and imposed sanctions on the republic. Trump’s “maximum pressure” campaign drove Iran into a spiralling recession, severely weakened reformists who backed the accord and emboldened hardliners who resisted engagement with the US.

Biden has promised to rejoin the deal if Iran falls back into full compliance with the agreement. But any chance of easing hostilities is complicated by Iran’s refusal to make concessions on its support for regional militant groups and its increasingly sophisticated missile programme.

Hemmati, a softly spoken technocrat who steered the central bank through the crisis, said Iran’s economy could endure the sanctions. But he added that the US’s punitive measures would prevent the republic developing at the pace needed to tackle Iran’s economic woes.

“We cannot have fast and solid economic development in a closed atmosphere. We need foreign technology, investments and finance,” he said. “Foreign policy should serve Iran’s economic development, which would be the number one priority of my government.”

Analysts say Hemmati’s only chance of victory is if Raisi is unable to secure more than 50 per cent of the vote. There would then be a run-off and pro-democracy Iranians might vote in larger numbers to support Hemmati.

His last-minute bid for the presidency gained significance after the authorities banned all the leading reformist candidates. But his campaign has been undermined by many Iranians’ sense of hopelessness after the turmoil of the past three years and what they perceive to be broken promises that the nuclear deal would bring prosperity and end years of isolation. As a result, many reformists’ supporters say they will boycott the election amid forecasts that turnout could be the lowest for a presidential contest since the 1979 revolution.

Iranian elections have a history of unpredictability and people close to Hemmati say they remain optimistic. But his hopes hinge on convincing disillusioned voters that their ballots can make a difference.

“The relationship between the people and the state has weakened — it is a fact. I have run to tell people it can change,” he said.

He described the vote as a “day of destiny”. “It can open some windows of hope for people, we should not let these windows close,” he said. “If that happens, it is not clear when they will open again and what will take place before these windows are reopened.”