Iranian Vice President Mohammad Reza Aref informed officials of plans to have him take charge of the nation during wartime, according to a report from the Iranian Students' News Agency (ISNA) published on social media late Saturday night.
There was no explicit note of President Masoud Pezeshkian's ability to carry out presidential duties.
Earlier on Saturday, security forces blocked roads in the Tehran area that is home to Pezeshkian's offices, witnesses said.
Israel may have killed dozens of senior Iranian officials, with Ali Khamenei as top target
Dozens of top Iranian officials may have been assassinated collectively at a few different meetings on Saturday, with indications that Israel focused on this part of the joint US-Israel bombings, while American forces focused on other issues, such as attacking the ballistic missile apparatus, naval targets, and nuclear targets.
The top-targeted official is Iran's Supreme Leader, Ayatollah Ali Khamenei.
His well-known command center in Tehran was bombed, but reports indicated that he was not there. However, Khamenei's daughter, grandchild, daughter-in-law, and son-in-law were killed in US-Israeli strikes, Iranian state media reported on Sunday.
Amichai Stein, Idan Kweller, and Reuters contributed to this report.