The Islamic Development Coordination Council said the ceremony will start at 10 PM tonight and that it will run for three days.
Planning for organizing the funeral for Ayatollah Seyed Ali Khamenei is also underway, according to the head of the council.
The Leader of the Islamic Revolution was martyred in a US-Israeli attack on his office in Tehran on Saturday.
Iran’s Cabinet of Ministers declared 40 days of national mourning following the martyrdom of Ayatollah Khamenei.
In response to the US-Israeli aggression, which has also led to the martyrdom of a number of senior military commanders and hundreds of civilians, Iran has launched Operation True Promise 4, carrying out massive missile and drone attacks on Israeli targets and US bases in the region.