From Reuters:

President Mahmoud Ahmadinejad has raised the stakes against Israel by describing the Holocaust as a lie, just as world powers are trying to decide how to deal with the nuclear ambitions of an Iran in political turmoil.
“The pretext (Holocaust) for the creation of the Zionist regime (Israel) is false … It is a lie based on an unprovable and mythical claim,” he told worshippers at Tehran University at the end of an annual anti-Israel “Qods (Jerusalem) Day” rally.
“Confronting the Zionist regime is a national and religious duty.”