(Front row, left to right) HM the Emperor of Japan, HM the Queen of the Netherlands, HM the Queen of Denmark, HM the King of the Hellenes, HM the King of Romania, HM Queen Elizabeth II of Great Britain, HM the King of Bulgarians, HM the Sultan of Brunei, HM the King of Sweden, HM the King of Swaziland, and HH the Prince Hans-Adam II of Liechtenstein. The middle row (left to right) HSH the Prince of Monaco, HRH the Grand Duke of Luxembourg, HM the King of Lesotho, HM the King of the Belgians, HM the King of Norway, HH the Emir of Qatar, HM the King of Jordan, HM the King of Bahrain, and HM The Yang di-Pertuan Agong of Malaysia. The top row (left to right) HH Nasser Mohamed Al-Jaber Al-Sabah of Kuwait, HH the Crown Prince of Abu Dhabi, HRH the Crown Prince of Yugoslavia, HM the King of Tonga, HRH the Crown Prince of Thailand, HRH Princess Lalla Meryem of Morocco and HRH Prince Mohammed bin Nawaf bin Abdulaziz Al Saud of Saudi Arabia.

King Tupou VI and Queen Nanasipau'u were among royals from the around the world who gathered in London on May 18, to celebrate Her Majesty Queen Elizabeth II's Diamond Jubilee.

The Telegraph reported, that Queen Elizabeth II welcomed sovereigns from 26 countries for a lunch at Windsor Castle on Friday, May 18. 

King Tupou VI and Queen Nanasipau'u also attended the Armed Forces Parade and Muster on May 19, in Windsor where over 2500 troops took part in the Diamond Jubilee Muster for the Queen.

King Tupou VI and Queen Nanasipau'u are scheduled to attend the 50th anniversary of Samoa's independence in Apia on June 1 before returning to Tonga, on June 4.