Japanese Emperor Naruhito formally took up his post on Wednesday a day after the abdication of his father, saying he felt a “sense of solemnity” but pledging to work as a symbol of the nation and the unity of its people.

Former Emperor Akihito and Empress Michiko stepped down after three decades in their roles on Tuesday in a brief and simple ceremony, with Akihito thanking the people of Japan and saying he prayed for peace.

Naruhito, 59, technically succeeded his father just as Tuesday became Wednesday but his ascension to the Chrysanthemum Throne was formalised in a mid-morning ceremony, the first part of which his wife and other royal women could not attend.

Naruhito, the first emperor born after World War II and the first to be raised solely by his parents, expressed gratitude for their work and said he felt solemn at the thought of the burden he is taking on.

“I pledge that I will always think of the people, and while drawing close to them, fulfill my duties as a symbol of the Japanese state and the unity of the Japanese people in accordance with the Constitution,” Naruhito, wearing a tailcoat and several large medals, said with a small smile.

“I sincerely hope for the happiness of the people and further progress of the country, and for world peace,” he said in the Imperial Palace’s “Matsu no Ma”, or Hall of Pine.

In the first stage of the ceremony, imperial chamberlains carried state seals into the hall along with two of Japan’s “Three Sacred Treasures” — a sword and a jewel — which together with a mirror are symbols of the throne. They are said to originate in ancient mythology.