Dame Susan Devoy says racism in New Zealand should be ignored "at our peril".
The Race Relations Commissioner was responding to a report from the weekend that an Iranian diplomat gave a fiery, anti-Israeli speech at an Auckland mosque in June, which has just come to light.
Jewish community leaders want Hormoz Ghahremani, first secretary of the Iranian Embassy, to be expelled after he spoke alongside Holocaust-deniers at the mosque.
Ghahremani said in his speech that Israel was trying to "deceive the world" and was fuelling terrorism and extremism in the Middle East to divert attention from the Palestine issue, reported Fairfax.
A rally was held in Wellington on Saturday, where Green MP Golriz Ghahraman gave an passionate anti-racism speech.