Iran's Assembly of Experts will meet within a day to elect a new supreme leader, according to assembly member Ayatollah Mozafari, quoted by Iranian media.
Ayatollah Ali Khamenei was killed in the first US-Israeli attacks on Iran last weekend. Iran's supreme leader has the final say in all matters of state.
The 88-member assembly is deciding who will take over the role after Khamenei's assassination. Under Iran's system of vilayat-e faqih - guardianship of the Islamic jurist - the supreme leader must be a senior leader with political and religious authority.
A three-person leadership council was formed to govern the country on an interim basis immediately after the death of the supreme leader.
It included:
-Masoud Pezeshkian, reformist president of Iran
-Gholamhossein Mohseni Ejei, the hard-line head of the judiciary.
-Alireza Arafi, lawyer and head of the Basij, a volunteer paramilitary force
