The details of solemn rite have been made public. The ceremony is set for 5pm in the "Matsu-no-Ma" (Room of Pine) in the presence of an ancient sword and a jewel, part of the imperial regalia. Akihito will remain sovereign until midnight. At that moment, a new imperial era will begin with Naruhito.
Tokyo (AsiaNews/Agencies) – Emperor Akihito’s abdication from at the Throne of Chrysanthemum will take a mere ten minutes. It is set for 5pm next Tuesday in the 370-square-metre "Matsu-no-Ma" (Room of Pine), considered the most elegant hall in the sumptuous Imperial Palace.
It is the only room with wooden floors – made from Japanese zelkova trees – rather than carpet, and the walls are covered with fabric featuring raised pine-leaf motifs.
The ceremony will be conducted in the presence of an ancient sword and jewel – part of the imperial regalia – considered crucial evidence of an emperor's legitimacy.
The sword and jewel will be brought in boxes into the room but a third element of the regalia, a sacred mirror, never leaves its sanctuary in the palace.
More than 300 people are expected to attend, including royals, government and parliament leaders, top judges, heads of local governments and their spouses.
Japanese Prime Minister Shinzo Abe will come forward and make a speech representing the people, before Akihito delivers his final official address as emperor.
This is the last occasion for the emperor to meet representatives of the people before he abdicates. Technically, he remains emperor until the clock strikes midnight.
At that moment, Prince Naruhito will formally ascend to the throne, and a new imperial era will begin, called "Reiwa" or "Beautiful harmony”.
The initial set of enthronement ceremonies takes place in the same Matsu-no-Ma at 10.30am on 1 May and are also very short.
During the first ceremony, the new emperor will inherit the sword, the jewel and the royal seals. The sacred mirror remains in the sanctuary but this time, an envoy is sent to offer a ritual prayer before it. This represents the emperor "inheriting" the mirror.
The emperor does not speak in this 10-minute ceremony, which is off-limits to female royals. Shortly afterwards, at 11.10am, Naruhito will take part in another ceremony in which he will pronounce his first speech as emperor. Again, Abe will speak on behalf of the people.
The new emperor greets well-wishers from a glass-covered balcony on 4 May but is then likely to keep a low profile until the autumn.
On 22 October, he will formally proclaim the enthronement with 2,500 participants from Japan and abroad in an official ceremony, followed by a motorcade through central Tokyo.
During the spring ceremonies, male royals are expected to wear Western-style coats and the women full-length dresses. But they will don traditional palace costumes for the autumn ceremonies and rites.