The heir of Iran's deposed monarchy predicted on Wednesday that the clerical regime will collapse within months and urged Western powers not to negotiate with it.
Reza Pahlavi said that major protests which erupted in November and again this month, after the accidental downing of a Ukrainian passenger jet, reminded him of the uprising that ousted his father in 1979.
"It's just a matter of time for it to reach its final climax. I think we're in that mode," the exiled former crown prince told a news conference in Washington.
"This is weeks or months preceding the ultimate collapse, not dissimilar to the last three months in 1978 before the revolution," he said.
While exiled activists have routinely predicted the fall of the regime, Mr Pahlavi said that Iranians could "smell the opportunity for the first time in 40 years this time".
Mr Pahlavi’s comments came as Iranians buried their dead from the air disaster as authorities on Wednesday identified more of the 176 victims.
Emotions have been running high amid mourning over the victims of the crash. The national flag was ripped from the coffin of one victim when relatives collected the body and the mother shouted "Tear it off," an online video post showed.
Protesters took to the streets of Iranian cities for four days after the armed forces finally acknowledged on Saturday, after repeated denials, that they had brought down the plane. In several places, demonstrators met a fierce police response.
Iranians on social media called for more protests on Wednesday, but there was no sign of the kind of rallies of previous days. Instead videos showed riot police massed outside universities, the focal point for demonstrations.
In earlier protests, footage showed police beating protesters, sounds of gunshots, teargas and blood on the ground.
"The government sees itself under siege from all sides right now and is not going to allow any protest to snowball into a nationwide movement," said Ali Vaez, director of the Iran Project at the International Crisis Group.
Iran is battling on several fronts. A new international crisis has erupted over its nuclear programme, the economy is in tatters under US sanctions and a long-running standoff with the United States briefly spiralled into open conflict.
In his address to the Hudson Institute, Mr Pahlavi largely supported President Donald Trump's "maximum pressure" campaign that has sought to isolate the Iranian regime through severe sanctions, saying that past negotiations have failed.
"It has long been time to recognise that this is not a normal regime and that it will not change its behaviour," Mr Pahlavi said.
"My compatriots understand that this regime cannot be reformed and must be removed."
Iranians "expect the world to show more than just moral support. They expect not to be thrown under the bus in the name of diplomacy and negotiation," he said.
Mr Trump previously held out hope of negotiations but has recently said he was unconcerned with talks and ordered the killing of a top Iranian general, Qassem Suleimani.
Mr Pahlavi, whose father was closely allied with the United States, has played down prospects for restoration of the monarchy.
He says instead that he wants to support a broad coalition of Iranians who will replace the regime with a secular democracy.
Asked whether he can represent all Iranians, Mr Pahlavi said: "It's not about me, it's about the people of Iran."
"You may not like the messenger, but is there something wrong with the message?"