Princess Anne proves spring is finally here in colour she rarely wears

Supporting her brother King Charles at his first Royal Garden Party of the season, Princess Anne looked amazing in a cobalt blue ensemble as she greeted members of the public at Buckingham Palace.

The Princess Royal, 73, stood out from the crowd as she took centre stage alongside the monarch, Queen Camilla, the Duke and Duchess of Edinburgh, and the Duke and Duchess of Gloucester. Dressed to the nines in her perfectly coordinated ensemble, Anne teamed her vibrant blue floral dress with a cropped boxy jacket featuring elegant button detailing.

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Perfect for spring, the silky, knee-length slip dress was paired with coordinating block heels and the royal's go-to accessory – suede gloves.

Princess Anne completed the timelessly chic look with a glittering brooch from her extensive jewellery collection and pinned a feathered fascinator in a similar sapphire tone to her updo.

The eye-catching shade of cobalt blue was somewhat of a departure for Zara Tindall's mother, who tends to favour pastel hues and muted floral prints over bold shades and big patterns.

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Queen Camilla, meanwhile, kept her look classic in a fit-and-flare white dress while Duchess Sophie was pretty in bubblegum pink.

Around 8,000 people were invited to the event in recognition of their service to local communities, charities, the military, and other organisations.

Garden Party etiquette

The Royal Garden Parties are one of the highlights of the monarch's summer calendar and were one of the late Queen Elizabeth II's favourite events.

Over the course of the spring and summer, King Charles will welcome over 30,000 guests at Buckingham Palace and the Palace of Holyroodhouse.

It's a chance for King and members of the wider royal family to mingle and chat with attendees from all walks of life.

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Enjoying the opportunity to explore the grounds, guests are able to eat and drink leisurely as they listen to the military bands play music.

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Historically, Garden Parties replaced presentation parties attended by debutantes, and are now a way of recognising and rewarding public service.

The dress code is smart, with gentlemen wearing morning dress or lounge suits, while women are invited to wear day dresses complete with hats or fascinators. Uniforms are also worn.