The US president and First Lady are currently in the UK undertaking a state visit, and the occasion was marked in style as they joined King Charles, 76, Queen Camilla, 77, Prince William, and Kate, both 43, at the Windsor Castle event. Kate looked dazzling, sporting a Phillipa Lepley silk crepe gown underneath a hand-embroidered gold Chantilly lace evening coat.

She also donned the late Queen Elizabeth II’s and the King’s Royal Family Order and a blue sash, representing that she is a Dame Grand Cross of the Royal Victorian Order.

Notably, she also wore the famous Lover’s Knot tiara, which was once owned by Princess Diana and was kept in a safe at Buckingham Palace after her 1997 death before it was handed to Kate.