Iranian President Mahmoud Ahmadinejad has called the Holocaust a "myth."
The Iranian government announced plans for the conference last weekend and said it would invite prominent Holocaust deniers to speak. Among those mentioned were German neo-Nazi Horst Mahler, the Israeli journalist and Christian convert Israel Shamir and the historian David Irving.
Politicians, especially in Germany, were up in arms at the idea of such a conference, Deutsche Welle said.
"This is international anti-Semitism at work," said Gert Weisskirchen, the foreign affairs spokesman for the Social Democratic Party in an interview with German magazine Der Spiegel.
Werner Hoyer from the free-market liberal Free Democratic Party told Der Spiegel such a meeting of Holocaust skeptics at a time of heightened tensions over Iran's nuclear ambitions was a "dangerous spark in the powder keg."
Shamir's Web state carried a post saying he had not been invited to the conference, has "knowledge whether such a conference will take place at all." The post said if an invitation is received "it will be considered carefully."