A child holding Japanese flags crosses a road ahead of a royal parade by Japan's Emperor Naruhito and Empress Masako in Tokyo, Japan, November 10, 2019.

Well-wishers wave Japanese flags during a celebration event to mark the enthronement of Japanese Emperor Naruhito in Tokyo, Japan November 9, 2019. Tomohiro Ohsumi/Pool via REUTERS.

Japan's Emperor Naruhito and Empress Masako ride in a car during their royal parade to mark the enthronement of Japanese Emperor Naruhito in Tokyo, Japan, November 10, 2019.

Japan's Emperor Naruhito and Empress Masako make an appearance during a celebration event, a day before Emperor and Empress' royal parade in front of the Imperial Palace in Tokyo, Japan November 9, 2019.

Japan's Emperor Naruhito and Empress Masako wave to well-wishers during their royal parade to mark the enthronement of Japanese Emperor Naruhito in Tokyo, Japan November 10, 2019.

A motorcade carrying Japan's Emperor Naruhito and Empress Masako rides during their royal parade to mark the enthronement of Japanese Emperor Naruhito in Tokyo, Japan, November 10, 2019, in this photo taken by Kyodo. Mandatory credit Kyodo/via REUTERS.

Well-wishers wave Japanese flags as Japan's Emperor Naruhito and Empress Masako make an appearance during a celebration event, a day before Emperor and Empress' royal parade in front of the Imperial Palace in Tokyo, Japan November 9, 2019.

J-pop group Arashi (Masaki Aiba, Sho Sakurai, Satoshi Ohno, Kazunari Ninomiya, and Jun Matsumoto) perform a song composed for the celebration event to mark the enthronement of Japan's Emperor Naruhito in Tokyo, Japan November 9, 2019. Kazuhiro Nogi/Pool via REUTERS.

Japan's Emperor Naruhito and Empress Masako ride in a car during their royal parade to mark the enthronement of Japanese Emperor Naruhito in Tokyo, Japan November 10, 2019.

Japan's Emperor Naruhito and Empress Masako wave to well-wishers during their royal parade to mark the enthronement of Japanese Emperor Naruhito in Tokyo, Japan November 10, 2019.

Japan's Emperor Naruhito and Empress Masako ride in a car during their royal parade to mark the enthronement of Japanese Emperor Naruhito in Tokyo, Japan, November 10, 2019.

Well-wishers holding paper lanterns and Japanese flags shout 'banzai' or cheers during a celebration event, a day before Japan's Emperor Naruhito and Empress Masako's royal parade in front of the Imperial Palace in Tokyo, Japan November 9, 2019.

Well-wishers wave lanterns and Japanese flags during a special event of celebration to mark enthronement of Japanese Emperor Naruhito in Tokyo, Japan November 9, 2019. Koji Sasahara/Pool via REUTERS.

People wait ahead of a royal parade by Japan's Emperor Naruhito and Empress Masako, in front of the Imperial Palace in Tokyo, Japan, November 10, 2019.

Japan's Emperor Naruhito and Empress Masako ride in a car during their royal parade to mark the enthronement of Japanese Emperor Naruhito in Tokyo, Japan November 10, 2019.

Well-wishers watch the royal parade to mark the enthronement of Japanese Emperor Naruhito in Tokyo, Japan, November 10, 2019.

Japan's Emperor Naruhito and Empress Masako make an appearance during a celebration event, a day before Emperor and Empress' royal parade in front of the Imperial Palace in Tokyo, Japan November 9, 2019.

A child waves a Japan flag as people wait for the start of a royal parade by Japan's Emperor Naruhito and Empress Masako, in front of the Imperial Palace in Tokyo, Japan November 10, 2019.

Honour guards make their way to the Imperial Palace ahead of a royal parade by Japan's Emperor Naruhito and Empress Masako, in Tokyo, Japan November 10, 2019.

Japan's Emperor Naruhito and Empress Masako hold lanterns during a national celebration to mark his enthronement at the entrance of the Imperial Palace in Tokyo, Japan November 9, 2019. Koji Sasahara/Pool via REUTERS.

A motorcade carrying Japan's Emperor Naruhito and Empress Masako rides during their royal parade to mark the enthronement of Japanese Emperor Naruhito in Tokyo, Japan November 10, 2019.

Japan's Emperor Naruhito and Empress Masako wave to well-wishers during their royal parade to mark the enthronement of Japanese Emperor Naruhito in Tokyo, Japan November 10, 2019.

Shrine parishioners from Saitama prefecture perform during a celebration event, a day before Japan's Emperor Naruhito and Empress Masako's royal parade in front of the Imperial Palace in Tokyo, Japan November 9, 2019.

People wait ahead of a royal parade by Japan's Emperor Naruhito and Empress Masako, in front of the Imperial Palace in Tokyo, Japan, November 10, 2019.

Shrine parishioners from Niigata prefecture perform during a celebration event, a day before Japan's Emperor Naruhito and Empress Masako's royal parade in front of the Imperial Palace in Tokyo, Japan November 9, 2019.

A man takes a photo of the Imperial Palace ahead of a royal parade by Japan's Emperor Naruhito and Empress Masako in Tokyo, Japan, November 10, 2019.

People wait for the start of a royal parade by Japan's Emperor Naruhito and Empress Masako, in front of the Imperial Palace in Tokyo, Japan November 10, 2019.

A woman holds a Japanese flag as she waits with others ahead of a royal parade by Japan's Emperor Naruhito and Empress Masako in Tokyo, Japan, November 10, 2019.

Dancers from Tokyo wearing traditional costumes perform during a celebration event, a day before Japan's Emperor Naruhito and Empress Masako's royal parade in front of the Imperial Palace in Tokyo, Japan November 9, 2019.

Shrine parishioners from Saitama prefecture perform during a celebration event, a day before Japan's Emperor Naruhito and Empress Masako's royal parade in front of the Imperial Palace in Tokyo, Japan November 9, 2019.

Well-wishers holding paper lanterns and Japanese flags shout 'banzai' or cheers during a celebration event, a day before Japan's Emperor Naruhito and Empress Masako's royal parade in front of the Imperial Palace in Tokyo, Japan November 9, 2019.