Kate Middleton's subtle nod to Princess Diana in candid new portrait

A new portrait of Kate Middleton has been released to mark the launch of her new photography book. Photo / Matt Porteous

The Duchess of Cambridge is about to launch her new photography book about life in lockdown.

And a new portrait of her released ahead of the book's launch reveals a sweet nod to her husband Prince William's late mother Princess Diana.

The stunning new photo was taken by Matt Porteous at Will and Kate's country home of Anmer Hall. It shows Kate smiling with a camera in hand and wearing a red sweater over a shirt with a white piecrust collar.

The neckline was named for the ruffled edges pastry chefs make with their thumbs and was made famous by Princess Diana in the 80s. Kate herself has been wearing the classic look on several recent outings.

It was one of Diana's favourite styles. She usually layered the collar under an overcoat or sweater to emphasise the ruffles, while Kate has gone for a more subtle style with fewer frills in more muted colours.

Kate's photography project, Hold Still, which captured Britain in lockdown as its people faced the Covid-19 pandemic, is being turned into a book titled Hold Still: A Portrait of Our Nation in 2020. It will bring together the final selection of 100 portraits along with the stories that go with the images.

Kate also wrote a moving foreword for the book, which was released alongside the photo.

"When we look back at the COVID-19 pandemic in decades to come, we will think of the challenges we all faced – the loved ones we lost, the extended isolation from our families and friends and the strain placed on our key workers," she wrote.

"But we will also remember the positives: the incredible acts of kindness, the helpers and heroes who emerged from all walks of life, and how together we adapted to a new normal."

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"Through Hold Still, I wanted to use the power of photography to create a lasting record of what we were all experiencing – to capture individuals' stories and document significant moments for families and communities as we lived through the pandemic.

"I hope that the final 100 images showcase the experiences and emotions borne during this extraordinary moment in history, pay tribute to the awe-inspiring efforts of all who have worked to protect those around them, and provide a space for us to pause and reflect upon this unparalleled period."

The book will be available online and in bookshops in the UK from May 7, one year since the project was first launched.

The net proceeds will be divided between mental health charity Mind, which Kate and William have supported for years, and the National Portrait Gallery.