Last Updated 3:01 p.m. Eastern.
Iran's opposition leader pledged Thursday not to withdraw his election challenge despite what he said were attempts to isolate and discredit him, while the declared winner of the vote, hardline President Mahmoud Ahmadinejad, accused President Barack Obama of meddling in Iran's affairs.
Reformist Mir Hossein Mousavi, who last led a protest rally a week ago, described his growing difficulties for the first time Thursday, in a statement posted in his official Web site, Kalemeh.
He said authorities were increasingly isolating and vilifying him in an attempt to get him to withdraw his election challenge.
In the latest sign of government attempts to silence dissent, 70 professors were detained late Wednesday after meeting with Mousavi, who has alleged massive fraud in the balloting. They were among a group pushing for a more liberal form of government, and all but four were released, his Web site said later. The four still in custody included Qorban Behzadiannejad, Mousavi's former campaign manager.
In a statement on his Web site Mousavi said he would not back down. "I am not ready to withdraw from demanding the rights of the Iranian people," he said, adding that he was determined to prove electoral fraud.
In a later statement, Mousavi struck an even more defiant tone.
"I am ready to show how the electoral wrong-doers, standing beside the main agitators that have caused the present disturbances, have spilled people's blood. I would not, for the sake of personal expediency and fear in the face of threats, withdraw for one moment my demands for the return of the rights of the Iranian people, whose blood is being unjustly spilled today."
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Since Saturday, demonstrators challenging the election results have found themselves increasingly struggling under a blanket crackdown by government authorities.
State media reported Thursday that in addition to the 17 protesters killed in the recent unrest, eight members of the pro-government Basij militia were killed and dozens more wounded by weapons and knives. The reports could not be independently verified.
A Thursday march by another opposition figure, reformist presidential candidate Mahdi Karroubi, was postponed for lack of a permit, a day after club-wielding security forces dispersed a small group of protesters outside Iran's parliament.
Mousavi's Web site, Kalemeh, said he has applied for permission to hold a gathering to commemorate the "martyrs" of the postelection campaign. The statement did not elaborate or give a date.
Mousavi, who last led a massive protest rally a week ago, described his growing difficulties for the first time in a statement on the site.
He said authorities were increasingly isolating and vilifying him to try to get him to withdraw his election challenge, but Mousavi added he would not back down.
Mousavi also defended himself and his movement, identified by the color green, against the barrage of claims on state media about foreign hands behind the unrest. "The green movement is not dependent on foreigners," he said.
The statement appears to conflict with a report on Iran's state-controlled TV network Press TV that Mousavi and his most powerful backer in the Islamic establishment, Ali Akbar Hashemi Rafsanjani, along with other reform-minded candidates, met with members of the Iranian parliament Wednesday.
Press TV's Web site said that, according to a lawmaker speaking to the Fars news agency, the men told members of Iran's Parliamentary Committee on National Security and Foreign Policy that they would help seek a resolution to the almost two weeks of political unrest.
"The lawmakers asked Ayatollah Hashemi-Rafsanjani to help solve the problems and he vowed support and we hope that we would witness practical measures to be taken to end the current situation soon," the lawmaker told Fars, according to the Press TV report.
EDITOR'S NOTE: Iranian authorities have barred journalists for international news organizations from reporting on the streets and ordered them to stay in their offices. This report is based on the accounts of witnesses reached in Iran and official statements carried on Iranian media.
Mousavi's statements came as Ahmadinejad reiterated complaints about foreign interference, singling out Obama and comparing him to former President George W. Bush, in a statement quoted by Iranian state television.
"We expect nothing from the British government and other Europeans governments, whose records and backgrounds are known to everybody and who have no dignity, but I wonder why Mr. Obama, who has come with the slogan of change, has fallen into this trap, the same route that Mr. Bush took and experienced its ending," Ahmadinejad said.
According to a report on the BBC, the Fars news agency quoted Ahmadinejad as saying Mr. Obama should "express regret" for what the Iranian regime has called interference in domestic affairs.
Before the Iranian election, the Obama administration had indicated that it was interested in reaching out to Iran, after years of a diplomatic freeze following the 1979 Islamic Revolution. Iran has given no clear signal that it is interested in Obama's overture. In the wake of the vote, Mr. Obama has used increasingly harsh language to discuss Iran, saying he was "appalled" by the clampdown.
Ahmadinejad, who is to be sworn in for a second four-year term by August, warned that there would be "nothing left to talk about" if the U.S. leader kept up such a tone. "This will not have any result, except that the people will consider you similar to Bush," he said.
The comments by both presidents could complicate any attempt at a dialogue, which Washington hopes will include talks on the scope of Iran's disputed nuclear program.
Key Western powers urged Iran's leaders anew to ease up on the protesters and review the disputed election results.
"We stand beside you," German Chancellor Angela Merkel said in remarks directed to "all in Iran who seek to demonstrate peacefully."
British Foreign Secretary David Miliband, whose government expelled two Iranian diplomats earlier this week after Iran did the same to two British envoys, told the British Broadcasting Corp. there is a "crisis of credibility between the Iranian government and their own people."
And Italy said it hoped Thursday's meeting of Group of Eight foreign ministers would send a "tough" message to the regime.
Ahmadinejad's standing at home appears to have suffered over the election dispute. Several Tehran newspapers reported that 185 out of 290 members of parliament, including Speaker Ali Larijani, stayed away from a victory celebration for Ahmadinejad on Tuesday.
However, there was also indications that the disputed election has caused a rift among former Ahmadinejad supporters. Several Tehran newspapers reported Thursday that only 105 out of 290 members of parliament attended a victory celebration held by Ahmadinejad on Tuesday. Among the no-shows was Parliament Speaker Ali Larijani.
Ahmadinejad's patron, Supreme Leader Ayatollah Ali Khamenei, has said the election result would not be reversed.
The fallout may leave Khamenei and the ruling theocracy battered by once-unthinkable defiance of their leadership. But they still control the Revolutionary Guard and its vast network of volunteer militias that watch every corner of Iran.
The Guard sworn to defend the Islamic system at all costs has been steadily expanding its authority for years to include critical portfolios such as Iran's missile program, its oil pipelines and other energy infrastructure, and some oversight of the nuclear program.
Iran's most senior dissident cleric, Ayatollah Hossein Ali Montazeri, warned the authorities in a statement that trying to snuff out dissent would prove futile.
If people are not allowed to voice their demands in peaceful gatherings, it "could destroy the foundation of any government," regardless of its power, wrote Montazeri. He was the heir apparent to the late Ayatollah Ruhollah Khomeini until falling out of favor with the ruling clerics by questioning their almost limitless powers. Montazeri spent five years under house arrest in the city of Qom, a center of clerical power and Shiite Islamic learning.
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