Spain's King Felipe VI addresses the UK-Spain Business Forum in London on July 13, 2017, the second day of his state visit. / AFP PHOTO / Tolga AKMEN        (Photo credit should read TOLGA AKMEN/AFP/Getty Images)
LONDON, UNITED KINGDOM - JULY 13:  Prince Harry, Queen Letizia of Spain, King Felipe of Spain and the Dean of Westminster Dr John Hall stand beside the grave of the Unknown Warrior during a State visit by the King and Queen of Spain at Westminster Abbey on July 13, 2017 in London, United Kingdom. This is the first state visit by the current King Felipe and Queen Letizia, the last being in 1986 with King Juan Carlos and Queen Sofia. (Photo by Francisco Gomez - Pool/Getty Images)
LONDON, UNITED KINGDOM - JULY 13: British Prime Minister Theresa May (L) meets His Majesty King Felipe VI of Spain (R) at 10 Downing Street in London, United Kingdom on July 13 , 2017. The meeting is part of the first state visit by King Felipe and Queen Letizia to the United Kingdom (Photo by Ray Tang/Anadolu Agency/Getty Images)
LONDON, ENGLAND - JULY 13:  King Felipe VI of Spain inspects a Guard of Honour before the Lord Mayor's Banquet at the Guildhall during a State visit by the King and Queen of Spain on July 13, 2017 in London, England.  This is the first state visit by the current King Felipe and Queen Letizia, the last being in 1986 with King Juan Carlos and Queen Sofia.  (Photo by Jeff Spicer - WPA Pool / Getty Images)
LONDON, ENGLAND - JULY 13:  (L-R) King Felipe VI of Spain, Queen Letizia of Spain and Andrew Parmley,Lord Mayor of London attend the Lord Mayor's Banquet at the Guildhall during a State visit by the King and Queen of Spain on July 13, 2017 in London, England.  This is the first state visit by the current King Felipe and Queen Letizia, the last being in 1986 with King Juan Carlos and Queen Sofia.  (Photo by Jeff Spicer/Getty Images)