The Japanese Imperial Family has long had close relations with the British Royal Family.
Emperor Emeritus Akihito has engaged in exchanges with the Royal Family since 1953, when he attended the coronation of Queen Elizabeth on behalf of Emperor Showa.
In 2012, the Emperor Emeritus, along with the Empress Emerita, visited Britain to attend the Diamond Jubilee to celebrate the Queen's 60th year on the throne.
Emperor Naruhito studied at Britain's Oxford University for two years from 1983. He lived in a dormitory and did research on the history of water traffic. He has since made official visits to Britain on three occasions.
The announced visit in the spring would be his first in 19 years.
Empress Masako also studied at Oxford University for nearly two years from 1988 after joining Japan's Foreign Ministry.
When Princess Anne, Queen Elizabeth's only daughter, visited Japan last October, the Emperor and Empress invited the princess and her husband to their residence.
On October 22 of last year, Prince Charles attended the enthronement ceremony of Emperor Naruhito and a court banquet at the Imperial Palace.