The death of Iran's Supreme Leader Ayatollah Ali Khamenei has left the country's succession in uncertainty.
Iran's constitution stipulates that an emergency council comprising the president, chief justice, and a senior cleric from the Guardian Council shall assume interim leadership when the supreme leader is incapacitated. However, the formation of such a council remains unclear as key figures including President Masoud Pezeshkian, Armed Forces Chief of Staff Abdolrahim Mousavi, Supreme National Security Council Secretary Ali Larijani, and Defense Commission Secretary Ali Shamkhani were among Israeli-U.S. airstrike targets. Israel has confirmed Shamkhani's death, according to CNN.
The New York Times reported last June that Khamenei, while in hiding during the "12-day war" with Israel, named three potential successors. Based on interviews with six senior Iranian government officials and two clerics, the candidates were Chief Justice Gholam-Hossein Mohseni-Eje'i, Chief of Staff Asghar Hejazi, and Hassan Khomeini, grandson of founding Supreme Leader Ayatollah Ruhollah Khomeini. Israel has confirmed that Hejazi was killed in the airstrikes.
Before his death, Khamenei delegated state management duties to Larijani and distributed political and military decision-making authority among select officials including his chief of staff, parliamentary speaker, and senior Revolutionary Guards figures, according to the Times. He also pre-designated succession orders for key positions.
Under the current constitution, the supreme leader is elected through deliberation by the Assembly of Experts and must be a cleric with expertise in Islamic jurisprudence.
Larijani was considered the most likely successor during Khamenei's lifetime. According to The Economist, Larijani represented Khamenei in negotiations with Russia, China, and Gulf monarchies more frequently than President Pezeshkian in recent years.
Born in 1958, Larijani is a former philosophy professor at Tehran University who studied mathematics and computer science before earning his doctorate researching German philosopher Kant. He served as parliamentary speaker from 2008 to 2020 and held four ministerial posts and Islamic Revolutionary Guard Corps command positions, giving him broad influence across Iran's governing system. His brother Sadeq Larijani served as chief justice from 2009 to 2019 and currently chairs the Expediency Discernment Council. However, hardline conservatives distrust Larijani for leading ratification of the 2015 nuclear deal, and he was previously barred from presidential elections by conservatives. Following the airstrikes, he posted defiant statements on social media.
Parliamentary Speaker Mohammad Bagher Ghalibaf, born in 1961, enjoys hardliner support. Ghalibaf has a stronger base within the Revolutionary Guards than Larijani and is reportedly close to Mojtaba Khamenei, the late leader's second son and a powerful behind-the-scenes figure. Some political forces favor Mojtaba as successor, though Khamenei himself opposed hereditary succession during his lifetime.
Reuters reported CIA analysis suggesting that Revolutionary Guards members or hardliners could take power if Khamenei were killed in a U.S. military operation. This analysis was conducted approximately two weeks before the attack.
Fox News cited experts saying Revolutionary Guards unity will be the key variable determining Iran's future direction. If the Guards and military maintain cohesion, existing power structures could largely remain intact, but internal fractures could open alternative political paths. No signs of division have been observed so far.
The existence of forces capable of replacing the current system also remains uncertain. Former Crown Prince Reza Pahlavi, born in 1960, has spent over 40 years abroad and is assessed to have a weak domestic base. Maryam Rajavi, leader of the Paris- and Albania-based opposition National Council of Resistance of Iran, called for forming a provisional government and action by "patriotic figures" within the military, though questions remain about whether they possess substantial support inside Iran.