King Charles III is being urged to cancel his upcoming visit to America. The former British ambassador to the U.S., Sir Peter Westmacott - who also served as His Majesty's deputy private secretary in the 1990s - believes Charles and Queen Camilla should call off their trip to see President Donald Trump amid the country's ongoing war with Iran. The 77-year-old and his wife are scheduled to make the journey across the pond next month to celebrate the 250th anniversary of America's independence. King Charles III and Donald Trump shake hands during the Republican's second state visit to the U.K.