Kate Middleton heralded the return of spring with her latest outfit, while out celebrating Commonwealth Day with her husband and family.

The Princess of Wales' fashion sense thrives in sunny weather, with her love of elegant and feminine outfits perfectly suiting the longer, brighter days.

The royal has been branching out even more with her recent looks, adding vintage pieces like her blue Chanel boucle jacket and toying with trending accessories like opera-length gloves. Her most recent appearance is no different.

Middleton attended the Commonwealth Day celebrations in London with members of the royal family. Photo: Getty

Middleton attended the Commonwealth Day celebrations in London with members of the royal family, debuting a new addition to her famous wardrobe.

The Princess stepped out in a retro-inspired navy blue suit by British design house Erdem, which is best known for their feminine designs with classic silhouettes. The eye-catching ensemble was part of the brand's autumn 2023 collection, meaning it won't be available for sale until at least August of this year.

Middleton wore a tailored suit jacket that featured a flounced peplum hem, cinched in waist and contrast darting on the bodice, making for a flattering hourglass silhouette. The jacket was paired with a midi-length skirt that was fitted through the hips and flared out into a feminine hem.

Middleton completed her look with tonal accessories, including a wide-brimmed navy blue hat. Photo: Getty

Both were created in a delicate and feminine jacquard print, which was one of many striking patterns in Erdem's latest collection that were inspired by Victorian wallpapers and fabrics.

Middleton completed her look with tonal accessories, including a wide-brimmed navy blue hat that dipped over one eye and was accented with a bow, as well as navy suede gloves. She added a pair of pointed toe stiletto heels by Gianvito Rossi.

She added some sparkle with precious diamond pieces from the royal family, including the Prince of Wales Feathers brooch, which is believed to be a gift from King Charles. She also wore a pair of sapphire and diamond drop earrings that were Princess Diana's, which match her engagement ring.

Her hair was worn swept into an up-do, while her makeup was kept fresh and dewy.