Japan's Emperor Naruhito and Empress Masako have left on an eight-day state visit to Britain.

The Emperor and Empress departed on a government plane from Tokyo's Haneda Airport on Saturday.

The Imperial couple were sent off by Crown Prince and Princess Akishino, Supreme Court Chief Justice Tokura Saburo, and the charge d'affaires ad interim of the British Embassy in Tokyo, among others.

They are scheduled to arrive in London on Saturday afternoon local time.

This is the Imperial couple's second state visit to a foreign country since Emperor Naruhito was enthroned in 2019.

The Emperor and Empress were officially invited by King Charles. They will attend a welcoming ceremony on Tuesday, as well as a banquet at Buckingham Palace.

The Emperor plans to visit the British royal family's tomb at Windsor Castle on Thursday to lay flowers at the grave of Queen Elizabeth II and her husband, Prince Philip.

The next day, the Emperor and Empress are scheduled to visit the University of Oxford, where they both studied.

The Imperial couple will return to Japan next Saturday.

The visit was initially scheduled for 2020 upon the invitation of the late Queen Elizabeth II. But it was postponed due to the coronavirus pandemic.