Ahmadinejad, in an address to the emergency Arab summit on Gaza violence in Doha, said Israeli leaders should be tried for war crimes in Gaza.
At the 22-member Arab League meeting, which Egypt and Saudi Arabia did not attend, he said: "It is most essential that Israel's political and military leaders stand trial for the acts of genocide they have committed against Palestinians."
After the meeting, a joint statement was issued to calling on Arab nations to cut ties with Israel over the Gaza attacks.
Iran's Supreme Leader Seyed Ali Khamenei has already urged Muslims to cut trade ties with Israel.
The Islamic Hamas movement receives strong backing from Iran, which also does not recognize the state of Israel.