Japan's Emperor Akihito has expressed his intention to abdicate, a government source said Wednesday.

His 56-year-old son, Crown Prince Naruhito, is expected to succeed the 82-year-old emperor and ascend the Chrysanthemum throne.

A government source said the Imperial House Law would require revision as it does not envisage abdication.

Throughout his reign spanning over 27 years, the emperor, together with his wife Empress Michiko, has continued to carry out his official duties, traveling throughout the country and overseas.

Emperor Akihito, the first emperor to accede to the imperial throne under Japan's post-World War II Constitution, has worked to encourage the nation through multiple disasters and made numerous trips to former battlegrounds at home and abroad to mourn the war dead.

Upon the death of his 87-year-old father Emperor Hirohito on Jan. 7, 1989, then Crown Prince Akihito ascended the throne at the age of 55. He was the first to do so as the "symbol of the state and of the unity of the people," a new status given to the world's oldest hereditary monarchy in the current Constitution, which came into effect in 1947.