LONDON, UNITED KINGDOM - MARCH 03: (EMBARGOED FOR PUBLICATION IN UK NEWSPAPERS UNTIL 48 HOURS AFTER CREATE DATE AND TIME) Home Secretary Theresa May attends the Ceremonial Welcome for Mexican President Enrique Pena Nieto at Horse Guards Parade during day 1 of his state visit on March 3, 2015 in London, England. The President of Mexico, Enrique Pena Nieto accompanied by his wife Senora Angelica Rivera de Pena, are on a State Visit to the United Kingdom as the guests of Her Majesty The Queen from Tuesday 3rd March to Thursday 5th March. (Photo by Max Mumby/Indigo/Getty Images)