Emperor Naruhito dropped into London's Japan House during 'private engagements' before official state visit began - with Empress Masako sitting out the visit to pace herself
Floods of people gathered outside to see Emperor Naruhito in London last weekREAD MORE: Empress Masako of Japan - who was dubbed 'a broken butterfly' due to ill health and struggles to adapt to imperial life - takes time out of visit
This is the sweet moment Emperor Naruhito was met with cheers from royal fans after a visit to Japan House on Kensington High Street last week.
The 64-year-old exited the building and waved at crowds of people who waited to catch a glimpse of him on Sunday, ahead of his official engagements with Empress Masako - which commenced on Tuesday.
The couple spent a few days enjoying 'a private programme of engagements' before an official welcome by Prince William on Tuesday, but the Empress did not appear to be present on the visit to Japan House.
In advance of the trip, doctors had warned that Masako would likely need to sit out some of the activities to preserve her energy - as she has done frequently through the course of her marriage - so the decision should come as no surprise.
On Monday, the Emperor made a private visit to the Thames Barrier - one of the largest movable flood barriers in the world - which is run by The Environment Agency.
Emperor Naruhito exited the building and waved at crowds of people who waited to catch a glimpse of the Japanese royal on Sunday
The royal has a passion for the river after studying water transport on the Thames in the 18th century while studying at Oxford University and even wrote a memoir about it, enttitled The Thames and I, which was published in 1993.
Crowds of people gathered outside for his visit to Japan House, with police and security guards on high alert and controlling crowds.
Royal enthusiasts were seen waving flags upon his exit, with some appearing to shout Naruhito's name to get his attention.
Naruhito looked dapper in a grey suit, crisp white shirt and tie as he stepped out in central London without his wife, Empress Masako, last week
Emperor of Japan waves to onlookers following a visit to the Francis Crick Institute
The emperor looked in high spirits as he paused to wave at the array of people before swiftly being ushered into a car as traffic on the busy Kensington street stood at a standstill.
Japan House is part of a global initiative led by the Japanese Ministry of Foreign Affairs, with two other Japan Houses located in Los Angeles and São Paulo.
It holds Japanese art, design, gastronomy, innovation and technology, along with various books from the country in a library.
Since opening in the summer of 2018, Japan House London has welcomed more than 1.7 million visitors, delivered 18 exhibitions and held over 900 events.
Naruhito visited the Francis Crick Institute today, a biomedical research centre where he had cell division explained to him by Sir Paul Nurse.
Empress Masako, was set to take some time away from the spotlight and won't attend visits after a rest day was built into the schedule for her, as their official engagements kicked off yesterday.
Behind the scenes, her role as Empress has always been a complicated one, beset by health issues and struggles to adapt in an imperial household that does not allow women to take the throne or continue royal duties if they marry a commoner.
Now, the state schedule for Wednesday will see the Emperor attend engagements alone.
Empress Masako (pictured yesterday) was set to take some time away from the spotlight and won't attend engagements after a rest day was built into the schedule for her
King Charles, Emperor Naruhito of Japan, Empress Masako of Japan, Queen Camilla and Prince William attend the Ceremonial Welcome yesterday
Floods of people gathered outside, with police and security guards on high alert and controlling crowds last week
The Empress is not set to attend tonight's banquet at the Guildhall hosted by the Lord Mayor and City of London corporation.
Naruhito will be joined by the Duke and Duchess of Edinburgh and is expected to make a speech - despite his wife not being by his side.
Yesterday evening, King Charles and Queen rolled out the red carpet for the Japanese royal couple by hosting a lavish State Banquet at Buckingham Palace.
Charles made a speech and referenced Japanese cultural icons, the characters Hello Kitty and Pokémon.
Reminiscing about the times he has been fly fishing with the Emperor, the king joked: 'I am only sorry to report that I haven't had any better luck with more recent attempts at fishing - the Pokémon phrase 'gotta catch 'em all' may resonate with my grandchildren, but for me it is, perhaps, aspirational!'
Highlighting the deep roots between the UK and Japan, he finished with a rousing 'Kan Pai' - cheers.
Emperor of Japan waves to onlookers following a visit to the Francis Crick Institute today
Naruhito also visited the Francis Crick Institute, a biomedical research centre where he had cell division explained to him by Sir Paul Nurse
For his part the Emperor expressed his 'sincere appreciation' for the invitation to visit and for the 'tremendous consideration and efforts that your and the people of the United Kingdom have shown in making it a reality.'
He alluded to the Second World War and the 'sad period during which the friendly relationship between our two countries suffered' but praised the now strong links and collaboration in areas ranging from politics and diplomacy to the economy, culture, arts, science and technology.
He concluded by describing the two countries as 'friends like no other'.
Their friendship was again shown yesterday when the King was presented with Japan's highest honour - the Collar of the Supreme Order of the Chrysanthemum.
King Charles III, (R), Japan's Emperor Naruhito, Empress Masako and Queen Camilla (L), pose for a group photo at the State Banquet
In return, the emperor was appointed to the Most Noble Order of the Garter, the highest order of chivalry in the UK.
Gifts were also exchanged, with Charles presenting the emperor with a bottle of artisanal, small batch release, single malt scotch whisky from the Japanese-owned Aberdeenshire distillery, Glen Garioch.
To accompany the whisky was a pair of silver and gold beakers by British goldsmith House of Benney, commissioned to feature both the Imperial Seal and the King's cypher.
The Queen presented Empress Masako with a handmade bespoke fan incorporating both Japanese and British good luck symbols.
It featured the Empress's crimson 'Ramanas' rose and the Queen's cypher and was made with wood from the branch of a fallen British plane tree in St James's Park, close to the Palace.
The guests also received a signed photograph of the King and Queen in a silver frame, and vice versa.
The empress presented Camilla with a Saga Nishiki brocade handbag.
Saga Nishiki is a Japanese traditional craft that was exhibited at the 1910 Japan-British Exhibition in London.
The King received a Wajima lacquerware Box from the emperor, who chose the gift in honour of those affected by the Noto Peninsula earthquake which hit Japan at the start of the year.