The Leader's body, along with those of his companions, was transferred to Tehran's Grand Mosalla early Friday and placed in the main prayer hall ahead of a two-day public farewell ceremony.
Religious scholars and cultural figures from Indonesia and Afghanistan were among the first foreign guests to pay tribute. Representatives of Iran's recognized religious minorities also attended the ceremony to honor the late Leader, who was assassinated in a cowardly US-Israeli strike on the opening day of the recent 40-day war on February 28
Foreign Ministry spokesperson Esmaeil Baghaei said Friday that delegations from nearly 100 countries, along with public figures and civil society groups, would attend the farewell ceremony for the martyred Leader.
"We have high-level delegations from neighboring countries. At least eight heads of government, including presidents or prime ministers, and parliamentary speakers from 12 countries will attend," Baghaei said. "Many other countries will be represented at the level of foreign ministers, other ministers, or special envoys."
He added that public groups and prominent figures from around 100 countries would also participate in the ceremony.
Baghaei said official delegations, public figures and members of parliament from Eastern European countries would attend the farewell ceremony. However, he said countries in Europe that had officially supported the military aggression by Israel and the United States against Iran had not been invited to attend the ceremony.
The public farewell, beginning Friday, follows a private ceremony held Thursday evening. Families of those killed in the recent war and relatives of staff members from the Leader's office gathered to bid farewell to the late Leader.
President Masoud Pezeshkian called on Iranians from all backgrounds to take part in the funeral ceremonies.
"As heroic Iran prepares to bid farewell to the sincere servant of Islam and the Revolution, I invite all people, regardless of ethnicity, religion, political taste or orientation, to participate with enthusiasm, dignity and in historic numbers, demonstrating a lasting image of national unity and loyalty to the lofty ideals of the Islamic establishment," he wrote in a message posted on X.
The multi-day funeral is expected to draw between 15 and 20 million mourners, according to Iranian officials.
Ceremonies will continue on Saturday and Sunday with the body lying in state at the Grand Mosalla before a funeral procession through Tehran on Monday. Further rites are scheduled in the holy city of Qom, followed by ceremonies in Baghdad, Karbala and Najaf in Iraq, before burial in Mashhad on July 9.
Meanwhile, Deputy Foreign Minister for Legal and International Affairs Kazem Gharibabadi said the anniversary of the downing of Iran Air Flight 655 and the remembrance of the late Leader both reflect enduring US hostility toward Iran.
"These days, alongside commemorating the martyrs of Flight 655, the Iranian nation also honors the memory of its martyred Leader," he wrote on X, adding that the Leader's martyrdom symbolizes both "the continuation and depth of America's hostility toward the Iranian nation" and "the enduring resistance of the Iranian people."
Iran marks July 3 as the anniversary of the 1988 downing of Iran Air Flight 655 by the USS Vincennes over the Persian Gulf, which killed all 290 people on board, including 66 children.
Iranian officials have long slammed the United States for refusing to issue a formal apology and for later awarding a medal to the commander of the warship.