The grandson of the man who led the religious revolution in Iran has called on the West to do more to support those who wish to end Islamic rule there.
Hossein Khomeini's views are attracting attention
In the same way that Winston Churchill mobilised an unconcerned population about Adolf Hitler, so could leaders such as US President George W Bush generate action inside Iran, Hossein Khomeini said.
"The best way is for the United States to help the movement for democracy in Iran," he said through a translator during a visit to Washington.
"They should look at this issue very seriously and not as dispassionately as they have been, waiting for something to happen and then get involved."
Correspondents say Mr Khomenei's criticism of Tehran's rulers is highly significant because he is himself a Muslim cleric and it attracts attention overseas because of his lineage.
Mr Khomeini told an audience at the American Enterprise Institute, a conservative thinktank, that he welcomed the US action against Saddam Hussein in Iran's neighbour Iraq even though he had not expected it until the US was faced by an immediate threat.
He railed against the "dictatorship" in Tehran and said the regime could yet give the US a reason for intervention. Though he had no knowledge that Iran was trying to develop nuclear weapons, he added: "I wouldn't put anything [past] them."
He said that while Iranian individuals had not been involved in terrorism recently, he believed the Tehran regime was a strong supporter of such activities and of working to destablilise both Iraq and Afghanistan.
He said the killing of Iraqi Shia cleric Ayatollah Muhammad Baqr al-Hakim and more than 120 others in a massive bomb attack outside Najaf's holiest shrine last month had been at the "behest" of Iran, with co-operation from Saudi Arabia.
Saddam Hussein loyalists and Osama Bin Laden's al-Qaeda are among those blamed for the attack by Iraqis and Americans.
Frustration of youth
Mr Khomeini recently left Iran, and has been spending time in Iraq, both in Najaf and Baghdad where he was outspoken in his criticism of the leadership in Tehran.
He told his American audience that Iranians - a vast majority of whom were under voting age or not yet born when an Islamic republic was voted in - had become frustrated but also enervated by the situation in his country.
"Today, Iranian people again want democracy, they want freedom. Furthermore they have experienced everything, they have experience theocracy in Iran and they have come to understand that religion and government cannot be one and the same."
Some ideas of the late ayatollah are not backed by his grandson
Mr Khomeini said he had been involved in the 1979 revolution led by his grandfather but about two years after the fall of the shah he began to question the practicalities of an Islamic republic.
He said Ayatollah Khomeini had himself only become converted to the idea of an Islamic republic with a supreme spiritual leader later in his life.
"I have differences with him," Mr Khomeini said of his grandfather. "[But] I have not fought with those who want that [theocratic regime], I'm simply against it."