Ali Khamenei's fatwa against nuclear weapons

A fatwa by Ayatollah Ali Khamenei, the Supreme Leader of Iran, against the acquisition, development and use 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 in August 2005.

Some analysts have questioned either the existence, applicability and/or constancy of the fatwa. According to Mehdi Khalaji, Khamenei may alter his fatwa under critical circumstances, as did his predecessor, Ayatollah Khomeini, on some civil and political issues. According to Gareth Porter writing in Foreign Policy, Iran's aversion to nuclear and chemical weapons is sincere because of the "historical episode during its eight-year war with Iraq", and Iran never sought revenge for Iraqi chemical attacks against Iran, which killed 20,000 Iranians and severely injured 100,000 more. According to Khalaji, the fatwa is also considered to be consistent with Islamic tradition.

The fatwa is included on Khamenei's official website, and it was referred to in remarks by both US President Barack Obama and Khamenei himself.

In 2021, acknowledging the fatwa, Iran's Minister of Intelligence said that the country may nevertheless change their stance if "pushed in that direction" like a "cornered cat".

At a meeting with the Islamic Republic's Foreign Ministry members on May 20th, 2023, Ali Khamenei said that entering the Joint Comprehensive Plan of Action, an agreement centered on restricting Iran's nuclear program, was taqiyah.