The Imperial Household Agency said Tuesday evening that it is making preparations for the engagement. In keeping with the current Imperial House Law, Princess Mako will leave the Imperial family when she is married.
Her prospective fiance is Kei Komuro, 25, a former fellow student at the university who now lives in Yokohama.
Shinichiro Yamamoto, grand steward of the agency, started answering reporters' questions at 8:30 p.m. Tuesday, saying, "Concerning the unofficial engagement, we were planning to announce it at the appropriate time." Yamamoto said that at the moment he wanted to refrain from saying when the announcement will be made.
According to Yamamoto, Komuro is studying business law at Hitotsubashi University's graduate school while also working at a law firm in Tokyo. Prince Akishino and his wife approve of the relationship, and the Emperor and Empress have been informed about it, Yamamoto said.
Following the announcement of the unofficial engagement, there will be a traditional rite of betrothal called Nosai no Gi, the equivalent of the ceremony traditionally held to exchange betrothal gifts among the general public.
This will be followed by other ceremonies held shortly before the wedding ceremony, including a ceremony in which Princess Mako and Komuro's marriage is reported to the Imperial ancestors and gods at three palaces within the Imperial Palace grounds, and Choken no Gi, in which the princess will bid farewell to the Emperor and Empress.
This will be the first engagement in 12 years of a naishinno princess - a daughter or granddaughter of the Emperor - since the engagement of the Emperor and Empress' daughter, Sayako Kuroda. It will also be the first time a female Imperial family member has become engaged in three years, since the wedding of Noriko Senge, the second daughter of the late Prince Takamado.
Princess Mako and Komuro met at a discussion meeting about studying abroad in June 2012 in Tokyo, and began to see each other, according to sources.
The princess was born in October 1991, making her the first grandchild of the Emperor and Empress. After entering Gakushuin Primary School in 1998, she went on to Gakushuin Girls' Junior and Senior High School. In 2010, she enrolled at the ICU College of Liberal Arts, where she majored in art and cultural heritage.
She studied at the University of Edinburgh in 2012, and after her graduation from ICU in 2014 participated in the University of Leicester's postgraduate program to study museology for about a year.
She is now an affiliate researcher at the University Museum of the University of Tokyo. In the summer of 2011, shortly after the nation was struck by the Great East Japan Earthquake, the princess visited affected places including Yamada and Otsuchi in Iwate Prefecture and Ishinomaki in Miyagi Prefecture and volunteered in activities to support children.
Since returning from Britain in September 2015, she has actively carried out such public duties as visiting facilities for people with disabilities and attending an international tennis tournament.
Komuro lives with his mother and grandfather. When he was a university student, he took part in tourism promotion activities for Fujisawa, Kanagawa Prefecture, serving as a "prince of the sea in Shonan Enoshima." His future dreams of "engagement in diplomacy" and hobbies including playing the violin, skiing and cooking were listed on the city's tourist association website.
Future fiance gives few details
Komuro, the soon-to-be fiance of Princess Mako, spoke with reporters Wednesday morning in Tokyo.
Because their engagement has not yet been officially announced, Komuro was restrained in answering questions about his relationship with the princess.
"When the right time comes, I would like to speak [with you all] again," he told the press.
Nevertheless, Komuro smiled when describing a phone conversation he had that morning with Princess Mako before leaving for work.
Komuro was accompanied by an official from the Imperial Household Agency when he spoke with reporters in front of the building that houses the law office where he works in Chuo Ward, Tokyo.
Looking somewhat tense, he bowed deeply for about two seconds, saying, "I apologize for making you wait for so long."
Komuro gave only brief answers when asked about his feelings, how he stayed in touch with Princess Mako and other matters.
"When the right time comes, I would like to speak [with you all] again," and "I apologize [but I cannot comment] at this time," he said.
When asked about media reports of his engagement, which appeared suddenly on Tuesday evening, he seemed perplexed by the sudden coverage.
"To be honest, I totally forgot where I saw it. I don't remember," Komuro said.
However, his expression softened when a reporter asked him what it was about Princess Mako's character that attracted him. He again avoided the question, but did reveal that the two had spoken briefly by phone before leaving for work that morning. He said he told her, "I'm off," and she responded, "Have a good day."
Asked about his current occupation, Komuro said he worked as a paralegal and is assisting lawyers. The legal office where Komuro belongs specializes in business turnaround and corporate law.
Komuro, who is proficient in English, deals with translations of contracts and research on the practice of law at the firm.
After taking a barrage of questions from the media for about six minutes, Komuro bowed deeply again and left with a smile.
Princess Mako left the Akasaka Estate a little after 10:30 a.m. by car for her job at a facility connected to the University Museum of the University of Tokyo. When she leaves the residence for private matters, she usually keeps the windows closed, but this time a rear window opened as the car passed through the gates.
She gave a shy smile and nodded in recognition to shouts of "Congratulations!" from the press corps.
The couple has already started preparing for their life after marriage, sources said.
Princess Mako is scheduled to make an official visit to Bhutan at the end of this month, so the agency is preparing to officially announce the engagement after she returns.
Under the current Imperial Household Law, princesses who marry must leave the Imperial family, which means Princess Mako would become a private citizen after marrying Komuro.
A senior agency official said the couple has already started preparations regarding a future residence.
(This story has not been edited by NDTV staff and is auto-generated from a syndicated feed.)