A top Iranian cleric said the key to restoring calm in the country is to free the detainees arrested during post-election protests against President Mahmoud Ahmadinejad, Mehr news agency reported on Friday.
Ayatollah Naser Makarem Shirazi, who has regularly voiced concerns over the political turmoil gripping the Islamic republic, said: "In order to bring calm to society, the fate of prisoners must be decided as soon as possible."
"Those who are not at fault or whose fault can be ignored under Islamic laws, they must be freed. I hope by the time of the birth anniversary of the 12th Imam (Mahdi), we will have no prisoners in the prisons."
The birth anniversary of Imam Mahdi, a revered Shiite saint, falls on August 7 and even Ahmadinejad has urged the judiciary to release all the protesters by then.
Earlier this week, Iran's chief proesecutor Ghorbanli Dorri Najafabadi said a "considerable" number of protesters would be released on Friday.
About 250 protesters still remain behind bars, as most of up to 2,000 people arrested in the post-election unrest have been released.
Twenty alleged "rioters" are due to go on trial from Saturday on charges including attacks on government and military offices.
The Islamic republic is engulfed in its worst crisis in its 30-year existence with anti-Ahmadinejad groups refusing to acknowledge his victory in the June 12 poll.