Iran has announced plans for a three-day funeral ceremony for Ayatollah Ali Khamenei, months after the former supreme leader's death and the subsequent postponement of burial arrangements, according to a report by The New York Times citing Iranian state media.

The Iranian authorities on Tuesday released details of the funeral programme for Khamenei, who was killed on the first day of the US-Israeli war against Iran, state media outlets reported.

Under Islamic tradition, funerals are generally held within days of a person's death. However, after Ayatollah Khamenei was killed in a joint strike by US and Israel forces, on his residence on Feb. 28, Iranian officials announced in early March that the funeral had been postponed indefinitely, citing logistical challenges linked to the large number of expected mourners.

According to Iran's state broadcaster IRIB, Tehran Deputy Mayor for cultural and social affairs Mohammad Amin Tavakoli-Zadeh said the farewell, funeral and burial ceremonies of 'Martyred Imam' are being finalised and will include three days of public ceremonies and processions across Tehran, Qom and Mashhad.

"The funeral ceremony in Tehran will last at least 24 hours," Tavakoli-Zadeh said, adding that authorities are preparing for as many as 20 million attendees in the capital.

He said that the venue is still being finalized and will be chosen between Tehran's Musalla (Grand Prayers Hall) and the mausoleum of founder of the Islamic Republic, Imam Khomeini.

Zadeh noted that the funeral procession in Tehran is expected to last at least 24 hours. Afterward, the body of the martyred Leader will be transferred to the holy city of Qom and then to Mashhad for similar ceremonies.

Based on recommendations made by relevant authorities, the final burial site of Ayatollah Seyed Ali Khamenei will be the holy shrine of Imam Reza (AS) in the northeastern city of Mashhad, he added.

The official explained that given Mashhad's geographical location, officials expect the city to host a massive number of foreign pilgrims, particularly from Pakistan, Afghanistan, India, Bangladesh, and the Kashmir region.

Khamenei was 86 when he was killed at an office within his home, bringing to an end more than three decades as Iran's supreme leader.

According to NYT, news of his death triggered mixed reactions in Tehran, ranging from disbelief and mourning to public celebrations.

Following his death, his son, Ayatollah Mojtaba Khamenei, was selected as his successor.

– Agencies