Emperor Akihito and Empress Michiko visited the tomb of Emperor Showa in Hachioji, western Tokyo, on Tuesday for an official ceremony to mark the Emperor's abdication on April 30.

The visit to his father's mausoleum in the Musashino Imperial Graveyard is among the 11 ceremonies scheduled for the 85-year-old's relinquishment of the throne and the last before rites to be held on the day of abdication.

The Emperor, wearing a morning suit, and the Empress, wearing a long dress, offered prayers at the mausoleum during the Shinetsu no Gi ritual. His father was known as Emperor Hirohito during his life.

Crown Prince Naruhito, 59, who will ascend to the Chrysanthemum Throne on May 1, will similarly take part in a number of ceremonies and rituals to mark his succession.

The abdication is the first by a living Japanese monarch in over two centuries.

As preparations for the Imperial succession move forward, the Cabinet of Prime Minister Shinzo Abe decided Tuesday to appoint the Crown Prince's top aide, Nobutake Odano, 71, as the new grand chamberlain as of May 1.

Current Grand Chamberlain Chikao Kawai, 66, will simultaneously assume a new post created to support the current Emperor after his abdication.

Odano is a former ambassador to the European Union, while Kawai is a former vice foreign minister.

The Emperor indicated his wish to abdicate in a 2016 video message. He cited his concern that he might not be able to fulfill his official duties due to his advanced age. The Diet enacted legislation the following year to enable the move.