King Charles III and Queen Camilla arrived on Monday at Joint Base Andrews near Washington aboard a plane bearing the Union Jack, before descending red-carpeted steps to begin their four-day visit.
They were welcomed by President Donald Trump and First Lady Melania Trump at the White House South Portico.
The two couples were set to share tea in the Green Room before heading outside to view a new White House-shaped beehive installed by the first lady last week.
later, Charles and Queen Camilla attend a garden party at the British ambassador's residence in Washington as part of a state visit to the United States, greeting numerous guests including Olympic diving champion Tom Daley, football player Esme Morgan and US House Speaker Mike Johnson.
