Donald Trump and wife Melania may have broken “royal protocol” during their UK state visit on 17 September. The pair arrived late to Windsor, keeping Prince William and Kate Middleton waiting.

Scheduled to meet at 12pm, Trump’s helicopter landed around 12:16pm, after King Charles III and Queen Camilla had already arrived. Though royal etiquette is optional, tradition encourages punctuality, bows or curtsies, and formal greetings such as “Your Majesty.”

Charles is known to dislike waiting, once muttering at his coronation about delays. After greeting the royals, the Trumps joined a carriage procession with 1,300 military personnel and 120 horses. Despite concerns over Camilla’s health, she attended. Later, Trump will inspect a guard of honour, attend a state lunch, and lay a wreath for Queen Elizabeth II.