Tehran's Friday prayer Leader Mohammad Ali Movahedi Kermani warned the ministers of culture and science on May 9 not to pursue policies of the era of former reformist President Mohammad Khatami.
"I warn the ministers of culture and science that our establishment should not return to the moral and cultural decadence of the reformist era," Ayatollah Movahedi Kermani was quoted as saying by Iranian news agencies.
Iranian hardliners strongly opposed Khatami's political and social reforms aimed at giving Iranians more rights and freedom.
The warning comes amid growing pressure from conservatives on Iran's President Hassan Rohani who is criticized over his nuclear and domestic policies.
In his sermons, Kermani called on authorities to enforce the Islamic hijab and not allow religious principles to be questioned by the country's media.
Based on reporting by Fars, BBC and Radio Farda