Iran's chief negotiator Mohammad Bagher Ghalibaf called on Thursday for massive turnout at Ali Khamenei's funeral to avenge the supreme leader's death in US-Israeli strikes at the start of the war.
"I invite all the Iranian people... to write a glorious page in the history of Islamic Iran through your presence" at the funeral ceremonies starting Saturday, Ghalibaf said in a statement, adding: "The nation's call for vengeance must ring in the ears of the whole world."
Khamenei's funeral, initially delayed at the height of the Middle East war, will take place as Iran and the United States observe a fragile ceasefire after signing a preliminary deal to halt the conflict.
Khamenei was killed at the age of 86 at his compound in the center of the Iranian capital on February 28, the first day of the war.
His public funeral will begin on Saturday, with his body lying in state at the colossal Grand Mosalla complex in central Tehran that hosts major Friday prayers, official ceremonies and religious gatherings.
The bodies of his slain relatives will also be presented.
Tehran, as well as the holy cities of Qom and Mashhad, which will host later stages of the funeral and burial ceremonies, will observe public holidays while the events are underway.
Authorities have ordered public and private offices in Tehran to close from Saturday through Monday, while traffic restrictions will make much of the city center inaccessible to private vehicles.
The airspace over Tehran will be partially closed from Friday and fully closed on Monday.
Following the ceremonies in Tehran, Khamenei's body will be taken to the holy Iraqi cities of Najaf and Karbala before his burial on July 9 at the shrine of Imam Reza in the northeastern city of Mashhad, his birthplace.