Interim Prime Minister Ehud Olmert labelled Iran's president a "psychopath" who "talks like Hitler" in an interview published on the heels of UN agency findings that the Islamic state hadn't adhered to limits on its nuclear program.
Olmert also told the popular German Bild tabloid in an article published Saturday that Iran would never attain a nuclear bomb.
"The West - above all under the leadership of the United States - will ensure that Iran under no circumstances comes to possess unconventional weapons," Olmert was quoted as saying. "The president of the United States is a very brave man who understands that very well."
Olmert's unprecedented attacks on President Mahmoud Ahmadinejad come as American and European leaders debate how best to curb Iran's nuclear ambitions.
Olmert's comments also follow by a few days Ahmadinejad's reiteration of his demonization of the Jewish State, which coincided with Holocaust Remembrance Day. Ahmadinejad has in the past denied the Holocaust, called on Jews to return to Germany, and declared that Israel should be wiped off the map.
"Ahmadinejad talks today like Hitler before he seized power" in Germany in the 1930s, Olmert said.
He added that Ahmadinejad's repeated calls for the destruction of Israel underlined the need to limit Iran's military strength.
"We are dealing with a psychopath of the worst kind. ... God forbid that this man ever gets his hands on nuclear weapons," Olmert was quoted as saying.
AP contributed to this report.