The Islamic Republic News Agency reported Khatami announced to reporters he would run against incumbent Mahmoud Ahmadinejad in the May 6 election.
"I would like to announce my candidacy for the upcoming presidential elections," Khatami was quoted by IRNA as saying.
Khatami supports more freedoms in the Islamic republic, The New York Times reported.
"The Iranian nation's historical demand is to have freedom, independence and justice, and I will work for that," Khatami was quoted by the U.S. newspaper as saying.
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