Japan's Emperor Naruhito plans to travel for the funeral of the Queen, while Prime Minister Fumio Kishida may also attend, Japanese media said.
It would be Naruhito's first overseas trip since acceding to the throne in May 2019.
Empress Masako has also expressed a wish to attend, and the Japanese government is arranging their trip, NTV, TBS and other media said on Friday, citing government sources.
Kishida is considering attending the funeral which is expected to be held in a little over a week, before visiting New York for the United Nations General Assembly late in the month, TV Asahi reported on Saturday.
US President Joe Biden has said he will attend the funeral of Britain's longest-reigning monarch.
The Queen, who visited Japan in 1975 to meet then-Emperor Hirohito, made a "great contribution" towards strengthening Japan's ties with Britain, PM Kishida said on Friday.
The British royals and Japan's imperial family have longstanding ties. The emperor had been invited to Britain by the Queen in 2020, but the trip was postponed due to the pandemic.
Naruhito, who studied at Oxford University as did Empress Masako, expressed his "deep sorrow and heartfelt condolences" over the death of the Queen in a statement released on Friday.
He praised Queen Elizabeth for guiding and encouraging the people of Britain and its Commonwealth nations.
"Her constant prayers for global peace and safety impressed many people around the world," Naruhito said. "I express my sincere respect and appreciation to many achievements and contributions that Her Majesty the Queen left behind."
The emperor and empress went into three days of mourning on Friday as they were feeling "deep grief and heartfelt condolences", the agency announced.
It is rare for a Japanese emperor to attend a royal funeral overseas.
In 1993, then-Emperor Akihito, now emperor emeritus, attended the state funeral of King Baudouin of Belgium with then-Empress Michiko.
The date for the Queen's funeral has not yet been confirmed by the Government.
This weekend, the Daily Mirror and Sunday Mirror celebrate the life of Her Majesty the Queen with a commemorative special filled with all the key moments from Britain’s longest reigning monarch. Be sure to pick up your copy of the Daily Mirror and Sunday Mirror to get both pullouts.
