Iran's charismatic former president, Mohammad Khatami, has declared he will run against the hardline incumbent, Mahmoud Ahmadinejad, in June's landmark presidential elections, dramatically enhancing the chances of rapprochement between Tehran and Washington after 30 years of bitter enmity. Mr Khatami, a soft-spoken philosopher-politician who is the standard-bearer and unifying figure of Iran's often fractious reformist movement, is regarded as the only candidate with enough popularity and respect to defeat Mr Ahmadinejad.
"I hope I can take steps to remove the people's problems and also enhance their position in the world," Mr Khatami, a middle-ranking cleric, said last night as he announced his decision. Repeating the electrifying mantra that won him a first landslide election victory 12 years ago, he said: "The Iranian nation's historical demand is to have freedom, independence and justice and I will work for that."
Those demands were the original centrepiece of the Islamic Revolution, whose 30th anniversary Iran is celebrating in desultory fashion. Most western and Arab diplomats in Tehran hoping for an end to Iran's nuclear standoff with the United States would be delighted to see Mr Khatami - who has long championed a "dialogue of civilisations" - back at the helm. He has hailed Barack Obama's victory as an opportunity to mend the three-decade-old rift between Tehran and Washington. The US president has offered a new approach to engage directly with Iran if the Islamic Republic would "unclench its fist".
During Mr Khatami's eight years in power from 1997 to 2005, he attempted to break down what he called the "wall of mistrust" with the United States. But he was thwarted by powerful Iran's old guard, who feared it would only make him more popular with a public longing to end Iran's international isolation. Domestically, Mr Khatami also struggled to liberalise Iranian society and politics but was stymied by a hardline minority whose power lay beyond the ballot box.
By the time Mr Ahmadinejad won his surprise landslide victory in 2005, the incremental gains under Mr Khatami's tenure, which included significant cultural glasnost, were mostly lost on a young and restless populace. Deep disillusionment set in with the reformist movement. But sympathisers always acknowledged that what Mr Khatami's critics saw as a weakness was actually a virtue: he refused to mobilise the immense people power at his disposal in case it led to the spilling of innocent blood on the streets.
Now Mr Khatami's time as president is regarded by many as a golden age. He oversaw a Tehran spring in which the media enjoyed unprecedented freedom, and where personal rights were expanded. Mr Ahmadinejad, with his back-to-revolutionary basics approach, has reversed most of those gains. "This time we will truly appreciate your presence," enthuses the last line of a theme song to go with an "Invite Khatami" campaign that had implored him to contest June's elections.
His former experience as president had made him deeply reluctant to run again. Friends and fellow reformists had been cajoling him to enter the fray for months. A sense of social obligation and concern for the direction of the Islamic republic under Mr Ahmadinejad had persuaded him to take on the presidential challenge, Tehran insiders said. The contest will polarise the Iranian electorate in what local commentators say will make as interesting a presidential contest as the one that recently gripped the United States.
"People feel the need for change because of Ahmadinejad's foreign policy and economic policies. Therefore people we think people will vote for Khatami, for change," said Mohammad Ali Abtahi, Mr Khatami's former chief of staff. Mr Ahmadinejad, a populist who promised to improve the lot of Iran's poor, has faced growing criticism over his economic mismanagement. Abroad, he has antagonised the West with his inflammatory rhetoric against Israel, which has deepened suspicions of Iran's cherished nuclear programme.