Iranian reformist cleric Mehdi Karoubi on Wednesday asked to meet top officials including the president to be able to present evidence of the rape of some detained post-election protesters, his party said.
The Etemad-e Melli website said Karoubi made the call in a letter to parliament speaker Ali Larijani, who has dismissed Karoubi's rape allegations last week as "baseless."
The meeting should be attended by Larijani, President Mahmoud Ahmadinejad, judiciary chief Ayatollah Sadeq Larijani, former president Akbar Hashemi Rafsanjani and the state prosecutor, Karoubi said.
"I ask you to organize a meeting ... in which I can personally present my documents and evidence over the cases of sexual abuse in some prisons," Karoubi said in the letter.
"I am waiting for your quick and rational action," he added.
Karoubi, who came fourth in the disputed June 12 presidential election, has come under fire from hardliners for saying some protesters, both men and women, were raped in jail.
Some have called for Karoubi to be arrested or tried if he failed to prove his allegations. Karoubi says he has evidence of mistreatment of detainees. Last Thursday, he said some of those arrested were killed under torture.
Opposition leader Mirhossein Mousavi, who came second in the vote, on Tuesday lent support to Karoubi and accused "establishment agents" of raping and abusing detainees, according to the reformist website mowjcamp.com.
"I praise your courage and hope the other clerics join and strengthen your efforts," Mousavi said in a letter to Karoubi.
Mousavi and Karoubi say the election was rigged to secure hardline President Mahmoud Ahmadinejad's re-election. Ahmadinejad and his allies deny it.
Iran arrested thousands of people after the election during its worst street unrest since the Islamic revolution three decades ago.
At least 200 people remain in jail, including senior moderate politicians, activists, lawyers and journalists. Iran has this month staged three mass trials against detainees.
"I tried to make the events related to the election more transparent and to defend the people's rights through my statements and letters," Karoubi said in his letter to Larijani.
"But unfortunately I did not receive a proper response ... Police, security and paramilitary officials insisted on their own firm position," he said.
The poll and its turbulent aftermath have plunged Iran into its biggest internal crisis since the 1979 Islamic revolution, exposing deepening divisions within its ruling elite and also further straining relations with the West.
Ahmadinejad is expected later on Wednesday to present a cabinet to parliament for approval but may get a rough ride from the conservatives who dominate the assembly, as well as from his moderate foes who see his next government as illegitimate.