UPDATED 6.27PM: Emperor Akihito, who has spent much of his nearly three decades on Japan's throne seeking to soothe the wounds of WWII, will step down on April 30, 2019 - the first abdication by a Japanese monarch in about two centuries.

A 10-member Imperial Household Council chaired by Prime Minister Shinzo Abe and including lawmakers, royals and supreme court justices agreed on the timing in a meeting on Friday.

The government was required by law to hear the council's views before formally deciding the date, most likely next week.

The octogenarian Akihito will be succeeded by his heir, 57-year-old Crown Prince Naruhito.

"This is the first abdication by an emperor in 200 years and the first under the (post-war) constitution," Abe told reporters after announcing the panel's recommendation.

"I feel deep emotion that today, the opinion of the Imperial Household Council was smoothly decided and a big step was taken toward the imperial succession."

Once considered divine, Japan's emperor is defined in the post-war constitution as a "symbol of the state and of the unity of the people", but has no political power.

Akihito, along with Empress Michiko, has spent much of his time on the throne trying to address the legacy of World War Two, which was fought in his father Hirohito's name, and consoling victims of disasters or other woes. He is widely respected by many average Japanese.

"Both the emperor and empress thought tirelessly about the people," said 72-year-old care-giver Taeko Ito. "Now he is elderly and I wish from my heart that he can have a rest."

Akihito and Michiko, the first commoner to wed a Japanese monarch, have worked to reconcile relations across Asia, which suffered from Japan's aggression before and during World War Two, with numerous visits abroad.

In 1992, he became the first Japanese monarch in living memory to visit China, where bitter memories of the war run deep. During that visit the emperor said he "deeply deplored" an "unfortunate period in which my country inflicted great suffering on the people of China".

Akihito has also consistently urged the Japanese people never to forget the horrors of war, remarks that have garnered increased attention since Abe took office in 2012 and sought to adopt a less apologetic tone over Japan's past military aggression.