Germany's foreign ministry is sending a clear message to Iranian President Mahmoud Ahmadinejad ahead of his Wednesday speech to the United Nations — don't deny the Holocaust.

If the rogue Iranian leaders does in fact make such a statement before the General Assembly, German diplomats will walk out. And Germany wants other European Union countries to follow, the foreign ministry was quoted by Reuters.

"We will leave the hall if President Ahmadinejad denies the Holocaust or makes anti-Semitic statements ... we are making efforts towards a unified European position," a spokesman told Reuters on Tuesday.

As recently as last week, Ahmadinejad has called the Holocaust a lie, repeating the inflammatory statement as world powers weigh how to deal with Iran's nuclear ambitions.

Stating that the Holocaust did not occur during World War Two is a crime in Germany. Last week Germany's Foreign Minister Frank-Walter Steinmeier condemned Ahmadinejad's most recent denial and called him a disgrace to his country, Reuters reported.