"Our mourning ceremonies for Imam Hussein should not make the enemies of Islam pleased since Imam Hussein is … the symbol of unity, so the ceremonies should not be used as platform for disunity," said Ahmad Khatami, addressing a Friday prayer service at Tehran University broadcast live on state radio.
Khatami, one of a small group of clerics who deliver the main weekly Friday prayers in Tehran, was appointed by Iran's supreme leader Ayatollah Ali Khamenei. He is also member of the Assembly of Experts, which selects the supreme leader and supervises his activities.
The 10-day Ashura ceremonies, which climax on Sunday, commemorate the death of Imam Hussein, one of Shiite Islam's most revered figures, at the hands of the armies of the Sunni caliph Yazid in 680 AD.
The ceremonies are marked in Shiite majority countries such as Iran and Iraq by processions in which mainly young men flagellate their bare backs with chains, as well as by mass gatherings of devotees chanting the praises of Imam Hussein.
The rituals gather momentum on Saturday and culminate on Sunday in crowded mourning ceremonies at mosques and in public places.
Deputy police chief General Ahmad Reza Radan said on Wednesday that his forces will crack down on any illegal gatherings during Ashura if they crossed the "red lines," without specifying what constituted the red lines.
Opponents of hardline President Mahmoud Ahmadinejad's controversial June re-election have recently used a series of major public events supported by the authorities to mount protests.
On Monday, hundreds of thousands of people poured onto the streets of the holy city of Qom for the funeral of dissident cleric Grand Ayatollah Hossein Ali Montazeri, chanting anti-government slogans and effectively turning the ceremony into an opposition rally, websites said.
Since then Tehran has clamped down on memorial services for the cleric, leading to clashes and arrests when mourners attempted to meet at a mosque for a service in the city of Isfahan on Wednesday, opposition websites reported.
