Ayatollah Ahmad Jannati said during Friday prayers at Tehran's main mosque that he wanted someone to shoot Foreign Minister Tzipi Livni.
A copy of the speech was also translated and published by the Middle East Media Research Institute, a Middle Eastern press monitoring service.
Jannati is the head of the powerful hardline Iranian Council of Guardians which ensures the government remains true to the principles of the Islamic revolution. This body is also in charge of approving parliament and presidential candidates, like Mahmoud Ahmadinejad, and okaying parliament laws based on the Iranian constitution's principles.
During the sermon, Jannati criticized Egypt and Syria in light of what he called "their silence over Gaza". According to the cleric, "Saudi Arabia isn't letting its citizens express their support for Gaza's residents."
He also slammed the United Nations Security Council resolution on Gaza, calling it "banal", but praised Venezuelan President Hogu Chavez for expelling the Israeli ambassador from Caracas.