U.N. Chief Calls on Iran to Free All Political Prisoners

U.N. chief Ban Ki-moon has called on Iran to free all its political prisoners, in a speech obtained by Agence France Presse on Friday and delivered in Tehran on the sidelines of a Non-Aligned Movement summit.

"I have urged the authorities during my visit this time to release opposition leaders, human rights defenders, journalists and social activists to create the conditions for free expression and open debate," Ban said, according to the text of the address delivered late Thursday to an Iranian diplomats' college.

Ban said that allowing the Iranian people's voice to be heard was especially important ahead of the country's 2013 presidential election, when a successor to President Mahmoud Ahmadinejad will be chosen.

"Restricting freedom of expression and suppressing social activism will only set back development and plant the seeds of instability," Ban warned.

The last presidential election in Iran in 2009, which saw Ahmadinejad declared the winner amid allegations by his challengers of fraud, was followed by widespread protests that were brutally crushed by authorities.

The figureheads of the opposition "Green Movement" have languished under house arrest ever since.

Iranian officials gave no immediate reaction to Ban's speech.

A brief state television report on the address referred only to the very last part of Ban's speech, in which he thanked Iran for giving him a Persian carpet as a gift.