Japanese Emperor Akihito’s 27 years on the ancient Chrysanthemum Throne have seen him reject the nationalism of World War II and stress the human face of the monarchy.

Now in the twilight of his reign, the slight, soft-spoken expert in fish science known as a modernising force for the ancient monarchy is again testing the tradition-bound world in which he has spent his entire 82 years.

In a rare video address to the nation he underlined his gradually declining health, which he said may eventually make it hard to fulfil his duties — hinting at a future abdication.

Akihito was born in 1933 just as Japan was embarking on its militaristic sweep across Asia, and was 11 when the war ended in defeat.

Under foreign occupation his father, wartime Emperor Hirohito, went suddenly from a semi-divine sovereign to national symbol.

Though the transition was difficult for his father, Akihito embraced the role and tried to use it to help heal the scars of the war while remoulding the ancient monarchy for a democratic age.