Princess Aiko, the only child of Emperor Naruhito and Empress Masako, has vowed on the occasion of her 20th birthday Wednesday to assist her parents as much as possible in their official duties now that she has come of age.

"I would like to refine myself and move forward step by step so that I can grow into an adult who can be of service to others," the princess said in a statement released by the Imperial Household Agency.

Official ceremonies to mark the princess's coming of age have been pushed back to the weekend to avoid disrupting her classes at Gakushuin University in Tokyo, where she is currently studying Japanese literature.