Naruhito formally ascends to the throne in a brief ceremony after his father, Akihito, ended his 30-year reign as head of the world's oldest continuing hereditary monarchy. On Wednesday, Naruhito took symbolic possession of the imperial regalia – a sacred sword and jewel – which were concealed inside decoratively wrapped boxes. No female members of the imperial family were permitted to attend, after the government controversially decided to honour precedents set by previous accession rites