Rafsanjani appeals to supreme leader

TEHRAN, June 10 (UPI) -- Cleric and former Iranian President Akbar Hashemi Rafsanjani expressed his concerns over the presidential campaign in an open letter to Iran's supreme leader.

In what is turning out to be one of the most hotly contested presidential elections in Iranian voting history, candidates are embracing an open forum to trade barbs on the campaign trail.

Incumbent President Mahmoud Ahmadinejad faces challenges from former Prime Minister Mir-Hossein Mousavi, former parliament speaker Mehdi Karroubi and former military commander Mohsen Rezaei.

In a rare live televised debate between Ahmadinejad and Mousavi, the two front-runners, the incumbent lashed out at Mousavi supporters, referring to "corrupt" officials in the former prime minister's camp, including Rafsanjani, who was defeated by Ahmadinejad in 2005.

Rafsanjani in an unprecedented move issued an open letter to Supreme Leader Grand Ayatollah Ali Khamenei, hoping to calm the "fire" stoked by the Ahmadinejad comments.

Rafsanjani calls the incumbent's statements "unfounded and irresponsible," referring to Ahmadinejad as an anti-Revolutionary leader whose statements run contrary to Islamic law, reports Radio Free Europe/Radio Liberty in its review of the Persian language letter.

Khamenei has remained on the sidelines during the presidential campaign, issuing statements calling only for a high voter turnout. Behind the scenes, he is expected to be an Ahmadinejad supporter, however.

Iranians head to the polls to vote for their next president Friday.