On the eve of turning 54 on Sunday, Crown Prince Naruhito praised the vital role the postwar Constitution has played in ensuring peace and prosperity in the country.

"Today's Japan was built with the Japanese Constitution as the cornerstone, and our country is now enjoying peace and prosperity," the Crown Prince, who is first in line to the throne, said at a news conference prior to his birthday.

Vowing to continue "respecting the Constitution" and act in compliance with it, the Crown Prince echoed the remarks of his father, Emperor Akihito, who also underlined the importance of the pacifist Constitution at a news conference to mark his 80th birthday late last year.

Under the Constitution, the Emperor serves as a symbol of the state and has no authority over national political affairs.

As for Princess Aiko, the Crown Prince's only child with Crown Princess Masako, he expressed hope his daughter will grow while being thankful and sensitive to other people, and become someone who can make her own decisions. The 12-year-old princess will graduate from Gakushuin Primary School in Tokyo this spring.

On Princess Masako, 50, who has been receiving treatment for a stress-induced illness for about 10 years, the Crown Prince said she is "getting better" but still "cannot immediately increase her activities."

Looking ahead to the 2020 Olympics and Paralympics that Tokyo will host, the Crown Prince said he is looking forward to the Summer Games becoming "an opportunity to make Japanese society vibrant and give children something to dream of."