The Princess of Wales expertly showed off her autumn fashion colour palette on Tuesday as she joined King Charles and Queen Camilla at Windsor Castle to formally welcome Sultan Haitham bin Tarik of Oman to the UK for the state visit.

As always, Catherine oozed elegance in a racing-green Sarah Burton for Alexander McQueen coat. The resplendent style has a belted waist and sharp, tailored detailing. The mother-of-three completed her look with a matching green Juliette Botterill hat and her sparkling Prince of Wales Feather Brooch. She also carried her vintage quilted Chanel handbag.

Later in the day, Catherine removed her coat to reveal a fabulous new frock - the 'Knitted maxi dress' in the same striking green by Norma Kamali. 

The style, which costs £250, is a beautiful, sleek style that fits close to the body and comes with a waist-cinching statement belt in the same striking hue.

Catherine chose the form-fitting style in the same seasonal green hue

A form-fitting dress is something we don't often see Catherine embrace. The royal mostly chooses dresses that have a little flare that gently skim her shape, as opposed to a sculpted shape.

Later that evening, the royal made a glittering state banquet appearance, comparable to Belle from Disney's Beauty and the Beast in her showstopping yellow gown.

Catherine's formal wardrobe is always magnificent, and she lived up to her chic reputation, donning a yellow creation by Elie Saab, which she paired with her go-to tiara: Queen Mary's Lover's Knot Tiara.

The Princess completed her regal look with the late Queen's earrings and bracelet, along with the King Charles III Royal Family Order, GCVO Sash and Star. 

Catherine last wore Elie Saab in 2023, at the royal wedding of Crown Prince Al Hussein bin Abdullah II of Jordan and Rajwa Al Saif. Her blush pink gown was one of her most memorable. The sugary-pink shade looked wonderful against her English-rose skin tone, and the lace details brought the expected regality.

Adding a neutral clutch bag to her look for the royal occasion, Catherine styled her hair in bouncy Hollywood curls and sported her usual natural makeup.