Ali Khamenei, who ruled the Islamic regime for nearly 37 years, was killed in a US or Israeli attack on his home in central Tehran on the first day of the war, February 28.
A three-day state funeral was initially planned for March 4, but was postponed until early June due to the war.
The ceremony is now scheduled to be held sometime between June 26 and July 5, the state news agency Fars reports, citing a statement from Tehran's mayor, Alireza Zakani.
Ali Khamenei's son, Mojtaba Khamenei, who has taken over the role of Iran's supreme leader, has not been seen in public since the outbreak of the war.
