By Robin Pomeroy and Ramin Mostafavi
TEHRAN (Reuters) - Could Mahmoud Ahmadinejad be Iran's last president?
Some Iranians think so after Supreme Leader Ayatollah Ali Khamenei suggested scrapping a directly elected presidency, which critics say would weaken Iran's version of democracy and make the Islamic Republic more Islamic than republican.
Ahmadinejad, whose second and final term ends in June 2013, dismissed Khamenei's proposal -- dropped into the middle of a lengthy speech -- as "academic" rather than a policy plan.
But clerics, politicians and analysts are taking it seriously enough to wonder whether Iran, whose bitterly contested presidential election in 2009 ignited months of street protests, will hold one at all in 2013.
"The announcement of this issue by the leader, especially at a popular gathering, cannot have been without great reason," Etemad newspaper quoted senior cleric Mohammad Reza Abbasi-Fard as saying.
Seminary teacher Mohsen Gharavian was blunter. "Ahmadinejad is the last president to be elected directly by the people," Abrar daily paraphrased him as saying. "Beginning in 2013 Iran's political system will undergo a change."
Ahmadinejad came to power in 2005, pulling Iran to the right after eight years of reformist President Mohammad Khatami.
His 2009 re-election was marred by alleged vote-rigging and plunged Iran into its worst turmoil since the 1979 revolution.
Reformists are considering boycotting a parliamentary election in March, which would undermine Iran's democratic credentials -- that critics say are already compromised by tight restrictions and vetting by unelected clerical bodies.
Initially seen as something of a Khamenei protege, Ahmadinejad has faced challenges this year from hardliners who fear his faction threatens the role of the clergy in Iran's unique form of government: a parliamentary system, with a directly elected president overseen by a powerful cleric.
Khamenei's assertion last week that there would be "no problem" in replacing the directly elected presidency with one elected by parliament has been welcomed by those who want to clip the ambitious Ahmadinejad's wings.
Parliament has grown more hostile to the president since his attempt in April, vetoed by Khamenei, to sack the intelligence minister, who plays a key role in overseeing elections.
Add to that concerns about a "deviant current" of presidential aides who often put Iran's Persian heritage on a par with its Islamic culture, and many religious hardliners would be happy to do without a headstrong president.
Abbasi-Fard, a former member of the state Guardian Council that vets presidential candidates, said it was Ahmadinejad's overbearing style that had pushed Khamenei to raise the idea of scrapping the elected presidency.
"If the megalomania and obstinacy continues," the supreme leader "might go beyond the (verbal) guidance and preaching" and push for the elected presidency to be abolished, Abbasi-Fard told Tuesday's Etemad in an interview.
This would signal the biggest constitutional change since 1989, at the end of the reign of revolutionary leader Ayatollah Ruhollah Khomeini, when the position of prime minister was abolished and that of president strengthened.
For Reza Marashi, an analyst at a Washington-based advocacy group, the National Iranian American Council, replacing a popularly elected president with one picked by parliament -- effectively turning him into a prime minister -- would further strengthen an already highly powerful supreme leader.
"Should Iran decide to eliminate the post of a directly elected president, the primary role of a reinstated premiership would be to execute the supreme leader's directives," Marashi wrote in an analysis published online.
"This was -- and continues to be -- what is expected from Ahmadinejad. His increasing intransigence has only sped up an otherwise steady moving process toward the domestic vision for Iran that many unelected officials hold: more Islamic than republican."
While most commentators in Iran see some merit in Khamenei's suggestion, in that it would reduce rivalry between president and supreme leader, one important figure has voiced misgivings.
Akbar Hashemi Rafsanjani, a former president and one of the central figures in the creation of the Islamic Republic, was quoted widely as upholding Iran's republican values.
"According to the constitution, republicanism and Islam are two unchangeable pillars of the Islamic Republic," said the cleric, who lost to Ahmadinejad in the 2005 presidential poll.
Such a major change would require a constitutional process, without which "undermining the republican aspect of the establishment is against the law and will restrict and limit people's power to choose," Rafsanjani said, adding:
"Of course the leader has entrusted this issue to a distant future in which it might be worth studying."
(Editing by Alistair Lyon)