Ali Khamenei's fatwa against insulting revered Sunni figures

On 30 September 2010, Iranian supreme leader Ali Khamenei issued a fatwa prohibiting the insulting by Shia Muslims of any of Hazrat Muhammad's companions, who are all held in high regard by Sunni Muslims without distinction. His fatwa came in the immediate aftermath of statements made by Kuwaiti Shia cleric Yasser al-Habib, who had publicly denounced Hazrat Muhammad's wife Aisha bint Abi Bakr and promoted celebrations of her death anniversary, which triggered a wave of intense backlash that negatively impacted Shia–Sunni relations. Al-Habib's remarks also prompted Kuwait to revoke his citizenship and sentence him to 10 years' imprisonment, but he had fled to Iraq and then to Iran before claiming asylum in the United Kingdom, where he remains stateless.

Khamenei's fatwa was met with widespread approval across the Muslim world. However, it received backlash from Shia Muslims who oppose the Islamic Republic of Iran, including al-Habib himself. Khamenei responded by condemning them as "MI6 Shias" for participating in and broadcasting activities that Sunnis regard as sacrilegious, such as insulting Hazrat Muhammad's companions and engaging in self-flagellation rituals. The incident gained much attention in Western media due to the Iranian government's accusation that Shia–Sunni tensions had been orchestrated by Israel and the Western world.

The fatwa is binding only upon those who tie themselves by taqlid (conforming entirely to a scholar's opinion) to Khamenei. As such, Shia Muslims following other maraji (highest Shia clerical rank) who disagree with the ruling are not obliged to treat it as binding and may even act against it. A number of prominent Shia Muslim scholars who share the opinion embodied in Khamenei's fatwa include Mohammad-Taqi Bahjat Foumani, Naser Makarem Shirazi, Abdul-Karim Mousavi Ardebili, and Mousa Shubairi Zanjani. Notable Sunni Muslim scholars who welcomed the fatwa include Ahmed Mohamed Ahmed El-Tayeb and Said Aqil Siradj.