Emperor, empress at Buckingham Palace

Emperor, empress at Buckingham Palace

LONDON, Britain - Japan's Emperor Akihito (L) and Empress Michiko arrive at Buckingham Palace in London on May 18, 2012, to attend a banquet hosted by British heir to the throne Prince Charles and his wife Camilla, Duchess of Cornwall. The imperial couple were visiting Britain to attend events commemorating Queen Elizabeth II's 60-year reign. (Pool photo)

Emperor, empress at Buckingham Palace

Emperor, empress at Buckingham Palace

LONDON, Britain - Japan's Emperor Akihito (L) and Empress Michiko arrive at Buckingham Palace in London on May 18, 2012, to attend a banquet hosted by British heir to the throne Prince Charles and his wife Camilla, Duchess of Cornwall. The imperial couple were visiting Britain to attend events commemorating Queen Elizabeth II's 60-year reign. (Pool photo)

Emperor, empress at Buckingham Palace

Emperor, empress at Buckingham Palace

LONDON, Britain - Japan's Emperor Akihito (L) and Empress Michiko arrive at Buckingham Palace in London on May 18, 2012, to attend a banquet hosted by British heir to the throne Prince Charles and his wife Camilla, Duchess of Cornwall. The imperial couple were visiting Britain to attend events commemorating Queen Elizabeth II's 60-year reign. (Pool photo)(Kyodo)

Emperor, empress at Buckingham Palace

Emperor, empress at Buckingham Palace

LONDON, Britain - Japan's Emperor Akihito (L) and Empress Michiko arrive at Buckingham Palace in London on May 18, 2012, to attend a banquet hosted by British heir to the throne Prince Charles and his wife Camilla, Duchess of Cornwall. The imperial couple were visiting Britain to attend events commemorating Queen Elizabeth II's 60-year reign. (Pool photo)(Kyodo)