Fatwa against nuclear weapons
A fatwa by Ali Khamenei, then supreme leader of Iran, against the development of nuclear weapons dates back to the mid-1990s. The first public announcement is reported to have occurred in October 2003, followed by an official statement at a meeting of the International Atomic Energy Agency (IAEA) in Vienna, Austria, in August 2005.
Source: Wikipedia — Fatwa against nuclear weapons (CC BY-SA 4.0)