Iranian opposition leaders are planning a united show of strength this week when they attend
Friday prayers in Tehran led by influential cleric and former president Akbar Hashemi Rafsanjani.
Defeated presidential candidates Mir Hossein Mousavi and Mehdi Karroubi said they will join hundreds of other worshippers as the two-time ex-president delivers a sermon for the first time in more than two months.
"I will join the lines (of worshippers) on Friday as I feel obliged to respond to the call of companions on the path to protecting rights to a noble and free life," Mousavi said on his website Ghalamnews.
It will be Mousavi's first public appearance in weeks after his supporters held massive street protests against President Mahmoud Ahmadinejad's bitterly disputed re-election on June 12.
In a first government reaction to the planned gathering, Intelligence Minister Gholam Hossein Mohseni Ejeie warned "Iranian people must be careful so that the Friday prayers is not turned into a venue for unpleasant scenes."
"Hopefully we will not have a security question in Tehran in the coming days," he told Fars news agency on Thursday.
Mousavi, who was Ahmadinejad's closest rival in the election but lost heavily to the incumbent, has charged that the June vote was rigged and dismissed the next government as "illegitimate".
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