The son of the deposed shah of Iran urged nations worldwide on Thursday to withdraw their ambassadors from Tehran to protest a relentless government crackdown on opposition demonstrators that resulted in at least eight deaths this week alone.

Reza Pahlavi, who has lived in exile since his father was toppled in the 1979 Islamic revolution, also appealed in a letter to U.N. Secretary-General Ban Ki-Moon for a U.N. investigation into human rights violations during the unrest.

In an interview with The Associated Press, Pahlavi equated the climate of the unrest in his homeland with the "revolutionary atmosphere" that preceded the fall of his father from the Peacock Throne 30 years ago, when the monarchy was replaced by an Islamic republic. The difference, he said, is that this time the people know what they want _ a secular democracy.

Pahlavi, like other members of the exiled opposition to Iran's clerical regime, is looking to play a role from afar as protesters brashly defy authorities in an increasingly tumultuous Iran.

In the letter Pahlavi urged the U.N. chief to press Iran to release those arrested and act to "halt the intolerable and increasingly dangerous march of events." The letter was given to the AP Thursday.

At least eight people died during protests Sunday, and hundreds were arrested in the worst unrest since the aftermath of June's disputed presidential election.

Pahlavi said that recalling ambassadors would be a "minimal but clear indication" by U.N. member states of their support for the rights of Iranian citizens and objections to violations of these rights by Iranian authorities.

"What you see in Iran is of major proportions," Pahlavi said by telephone. Based in the United States, the 49-year-old former crown prince is currently in Europe. His exact location was not divulged for security reasons.

"I can equate it with the same kind of climate that existed toward the end of 1978, 30 years ago, which led to a revolutionary atmosphere which I think has been reached right now in Iran," he said.

Shah Mohammad Reza Pahlavi was overthrown Feb. 11, 1979. He fled Iran and wandered from country to country, ill with cancer and eventually died in Egypt in 1980. His son is based in Bethesda, Maryland, but often travels to France.

"The biggest difference is if yesterday the only focus was on bringing down the previous regime, while most people didn't quite know what it would end up like, this time people not only know what they don't want, which is the current regime, but they also know what they want," the shah's son said.

He said he believes the great majority want a secular democratic system to replace the clerical regime.