Apologists for the Islamic Republic in the U.S. such as Reza Aslan of the mullahs' lobbying group, the National Iranian American Council (NIAC), have denied that he said this in the past, claiming that it was "mistranslated." The problem for them is that he keeps saying it. "Ahmadinejad again calls to 'wipe Israel off the map,'" from [1] Elder of Ziyon, November 24 (thanks to Lachlan):

From the official Iranian [2] Mehrnews Arabic site:

Iranian President Mahmoud Ahmadinejad said that resolving the Palestinian issue does not need war, but requires a unified Islamic decision to remove the Zionist entity off the map.

Again, this is the official translation from Iran, and it has been copied by many [3] Arabic newspapers.