TEHRAN, (Reuters) – Iran staged a conference on Monday to debate the Holocaust and question whether Nazi Germany used gas chambers, prompting charges it was encouraging the denial of the killing of 6 million Jews from 1933 to 1945.

Guests at the government-run event, titled “Review of the Holocaust: Global Vision”, included Westerners who have cast doubt on the Holocaust — some of them from countries that have made it a crime to deny it happened — as well as a few Jews. “The aim of this conference is not to deny or confirm the Holocaust,” Foreign Minister Manouchehr Mottaki said. “Its main aim is to create an opportunity for thinkers who cannot express their views freely in Europe about the Holocaust.”

The two-day conference at a Foreign Ministry institute was inspired by President Mahmoud Ahmadinejad, who since coming to power in August 2005 has sparked international condemnation by terming the Holocaust a “myth” and calling Israel a “tumour”.

Ahmadinejad has said he wants to encourage scholarly debate and examine the justification for Israel’s creation.

American David Duke, a former Ku Klux Klan leader, praised Iran. “There must be freedom of speech, it is scandalous that the Holocaust cannot be discussed freely,” he said. “It makes people turn a blind eye to Israel’s crimes against the Palestinian people.”

Israel, the United States and a leader of Iran’s own 25,000-strong Jewish community condemned the conference. Israeli Prime Minister Ehud Olmert called it “a sick phenomenon that shows the depth of hatred of the fundamentalist Iranian regime”.

“The enlightened world must condemn this conference and the one who has convened it in the most determined matter. There can be no compromise regarding such a phenomenon,” he told reporters en route to Germany.

The U.S. State Department last week denounced the gathering as “disgraceful”. Moris Motamed, the sole Jewish representative in Iran’s parliament, described it as a “huge insult”.

Many ordinary Iranians admitted to embarrassment about the event, which follows Iran’s decision to hold a competition for cartoons about the Holocaust in October. But French writer Georges Thiel, who has been convicted in France for spreading revisionist theories about the mass extermination of Jews, told the conference the Holocaust was “an enormous lie”. “Jewish people have been persecuted, that is true, they have been deported, that is true, but there was no machinery of murder in any camp — no gas chambers,” he said.

Participants included about half a dozen Jews from Europe and the United States clad in long black coats and black hats, some wearing badges depicting the Israeli flag crossed out. One wore a badge saying: “A Jew, not a Zionist”. “We came here to put the Orthodox Jewish viewpoint,” said British Rabbi Ahron Cohen. “We certainly say there was a Holocaust … But in no way can it be used as a justification for perpetrating unjust acts against the Palestinians.”

A former senior Iranian government official, who declined to be named, said that hosting the conference was unwise given diplomatic pressure on Iran over its nuclear programme. “Such conferences should not be held,” he said.

An Israeli Arab who founded his community’s first Holocaust memorial said Iran refused let him come. Iran denies visas to Israeli passport holders or anyone with an Israeli visa stamp. “I am disappointed because I wanted to go to the conference and confront those who denied the Holocaust had taken place,” lawyer Khaled Mahameed told Reuters by telephone.