by Simon Tisdall for The Guardian

The man accused by Mahmoud Ahmadinejad of masterminding the opposition campaign to oust him from the presidency has dropped out of view since election day. But Ali Akbar Hashemi Rafsanjani remains a formidable figure in Iranian politics with a network of well-placed allies straddling the reformist and moderate conservative camps. If any one leader is able to force a re-run of last Friday’s disputed poll, it may be the two-term former president nicknamed the “shark”.

Rafsanjani was last heard from in public as he cast his vote on Friday. According to the Iranian Students News Agency, he called for a “clean” poll and said a big turnout (favouring the reformists) would boost Iran’s regional and international image. Following the ensuing storm over Ahmadinejad’s apparent victory, al-Arabiya television reported Rafsanjani had resigned as chairman of the Assembly of Experts and of the Expediency Council, two key government bodies. This report remains unconfirmed.

More intriguing are similarly unsubstantiated claims that Rafsanjani is in the holy city of Qom, where he once studied and where he has strong links to a moderate clerical body, the Association of Combatant Clergy. Rafsanjani was said to be assessing whether he has sufficient votes in the 86-member Assembly of Experts to dismiss Ayatollah Ali Khamenei, the Supreme Leader and Ahmadinejad’s chief patron. Under Iran’s constitution, only the assembly has the power to do this.

The super-rich Rafsanjani, his family, and his supporters in the reformist Kargozaran party make no bones about helping finance and direct Mir Hossein Mousavi’s campaign to topple Ahmadinejad, whom they despise. But with Mousavi ostensibly beaten, the developing post-election struggle now pits Rafsanjani against Khamenei rather than the president – who is widely seen as a mouthpiece for the hardline fundamentalism typified by the Supreme Leader. Although he is supposed to stay above the fray, Khamenei endorsed Ahmadinejad this time, just as in the second round of the 2005 election.

Rafsanjani has made no secret of his belief that foreign and economic policies pursued during the past four years under Khamenei’s guidance have seriously damaged the Islamic Republic. His frustrations came to a head last week after Ahmadinejad was allowed to publicly accuse him of corruption. In an angry letter he lambasted Khamenei for failing to uphold the country’s dignity. In what was in effect an unprecedented challenge to Khamenei’s authority, he implied the Supreme Leader, normally above criticism, was negligent, partial, and possibly involved in plans to steal the election.

“I am expecting you to resolve this position in order to extinguish the fire, whose smoke can be seen in the atmosphere, and to foil dangerous plots,” Rafsanjani wrote. “If the system cannot or does not want to confront such ugly and sin-infected phenomena as insults, lies and false allegations, how can we consider ourselves followers of the sacred Islamic system?”

Rafsanjani remains unpopular with many Iranians who believe the corruption claims and blame him for a murderous, covert campaign to silence dissidents at home and abroad during his 1989-97 presidency. Those latter allegations earned him another nickname: the “grey eminence”. At the same time he is respected as one of the Islamic revolution’s founding fathers and a close associate of its first leader, Ayatollah Ruhollah Khomeini. As a result he can count on some powerful friends if he decides to try to shame Khamenei into allowing an election re-run or standing down.

Apart from his clerical allies in Qom, prominent establishment conservatives such as Ali Akbar Velayati and Ali Akbar Nateq-Nuri have criticised Ahmadinejad. So, too, has Ali Larijani, the influential Majlis (parliament) speaker and former national security chief. The mayor of Tehran, Mohammad Bagher Qalibaf, is another potential ally, as are the former president Mohammad Khatami, Mousavi, the other defeated presidential candidates, and their millions of thwarted supporters.

If mobilised, his would comprise an elite coalition operating inside the hierarchy of the Islamic Republic, rather than from outside on the streets. It would not be a democratic movement; but it would be a dagger held to Khamenei’s breast. Not for nothing is the Machiavellian Rafsanjani, pistachio nut millionaire, pragmatist and ruthless political survivor, known by yet another nickname: the “kingmaker”. Iran awaits his next move.