The Princess of Wales looked sensational last week, wearing a floor-length Givenchy gown and the dazzling Lover's Knot tiara for President Macron's state visit, bringing glamour to proceedings and cementing her role at the heart of "Brand Britain".
Kate joined the King and his family for a state banquet for the first time since November 2023, which was only weeks before she was admitted to hospital for abdominal surgery.
She appeared polished, poised and happy to be at Prince William's side as they played a major part in the diplomatic charm offensive.
Royal watchers were thrilled by the outing, which took place a week after the Princess opened up about the challenge of finding "a new normal" after cancer treatment.
"The Princess's importance to Brand Britain is huge and her presence at these events gives them a vibrancy and an energy," said the royal author Robert Jobson.
President Macron, who was spotted winking at Kate during the glittering white-tie banquet, was clearly thrilled to sit next to her.
"The interaction between her and Macron sort of says it all, doesn't it? There's a story there, there's an interest," said Robert. "Her presence is really important and it will be the same when President Trump visits in September."
Taking part in her first state visit at Windsor Castle, Kate displayed impeccable sartorial diplomacy in a dark red silk creponne gathered evening gown with caped back detailing designed for Givenchy by Sarah Burton, who created her wedding dress while at the helm of Alexander McQueen.
She wore it with a lily of the valley embroidered evening clutch, earrings once owned by Diana, Princess of Wales, a necklace from the late Queen Elizabeth's collection and the dazzling Lover's Knot tiara.
Earlier in the day she had showcased another French fashion house, joining William to greet the President and First Lady at RAF Northolt in a dusky pink 30 Montaigne Rose Des Vents jacket by the designer Maria Grazia Chiuri for Christian Dior, inspired by one designed in 1947 by Christian Dior himself.
The future King and Queen exchanged plenty of loving glances and each put a hand on the other's back at various points throughout the day.
"They look very much at one together and they look a bit more serious," says Robert, author of the biography Catherine: The Princess of Wales. "They realise they have a serious role to play and we’re seeing them having grown into that role more than ever before."
But while Kate was front and centre at last week’s events, in recent weeks she has been careful to strike a balance between her return to public life and the need to prioritise her young family and health after undergoing cancer treatment last year.
After pulling out of an expected appearance at Royal Ascot last month, she spoke candidly about needing to come to terms with a "very scary, very daunting experience" on a visit to Colchester Hospital on 2 July.
"There is a whole phase when you finish your treatment, everybody expects you to be better – go! But that's not the case at all," she said.
"You put on a sort of brave face, stoicism through treatment. Treatment's done, then it’s like 'I can crack on, get back to normal' but actually the phase afterwards is really difficult…You have to find your new normal and that takes time."
"She was making a point of saying, 'This is on my terms'," Robert tells HELLO! "I think she was trying to explain why she hadn't appeared at Royal Ascot, but also how things might look after her cancer experience.
"She knows every word will be listened to and she knows what can be heard and what can’t be heard. And she's careful and confident in what she says. I think people need to accept that they may not see her as often as they used to – for now."
Robert, who has been covering the royal family for four decades, believes the Princess will continue to carefully protect her work-life balance until William becomes King.
"As Queen, Kate will be one of the most talked about and most photographed women in the world," he says. "And at some point in the future she and William will be public property. So I think she will continue to prioritise this time with her children while they are young and William is supporting that. I think it's a case of them knowing they have limited time to do this."
The Prince is naturally intensely protective of his wife, who did not grow up in the spotlight as he did.
"There's a hunger, a demand, that's probably too much," adds Robert. "William saw it first-hand with his mother, Diana – how it can become too hard to handle, too difficult an existence to have – so you have to manage it. I think they've done it pretty well.
"Kate sharing her diagnosis was a very powerful moment. It showed everybody she needed space."
But as last week's major public moments proved, her presence brings added star power to any royal event.
"It changes the whole vibe of the occasion," says Robert. "People want to see her, what she wears and what she does. She really is key in terms of the continuity of the family. William is likely to have a long reign and I think that, at his side in the future, Kate will be one of the most talked about Queens in the world."
The royal family had rolled out the red carpet for the French President with a glittering state banquet in St George's Hall at Windsor Castle, which was attended by famous faces including Sir Elton John and David Furnish, Sir Mick Jagger and Melanie Hamrick, and Dame Kristin Scott Thomas.
The footballer Mary Earps, sculptor Antony Gormley and authors Joanne Harris and Sebastian Faulks were among the guests, as was Fred Sirieix, the French star of the British show First Dates.
The Queen looked regal in an ivory silk and crepe embroidered evening gown by Fiona Clare, and a sapphire and diamond tiara, necklace, earrings, and bracelet from Queen Elizabeth II’s sapphire suite.
She also wore the Legion d'Honneur French sash, Garter Star and the Royal Family Order of King Charles III.
The Duchess of Edinburgh wore a bespoke white sequin gown by Suzannah, while the Princess Royal also wore white.
In a toast, made in English and French, the King reflected on 1,000 years of "shared history and culture between our two peoples".
He also referenced his own family’s long ties with France – describing how construction of the castle was started by his ancestor William, Duke of Normandy, in 1070.
"So it is perhaps rather appropriate that my son, the Prince of Wales, who shares that earlier William's name, has made Windsor his home with his family, like so many of our predecessors," he said.
Charles hailed the "truly modern partnership" between both countries, saying: "As we dine here in this ancient place, redolent with our shared history, allow me to propose a toast to France and our new Entente. An Entente not only past and present, but for the future – and no longer just cordiale, but now amicale."
President Macron thanked the King for his "great courtesy" and paid a fulsome tribute to the late Queen Elizabeth II.
Guests enjoyed a seasonal menu that included a starter and dessert course designed by the French chef Raymond Blanc, while the wine list included Domaine Evremond Classic Cuvée Brut Edition 1 NV, an English sparkling wine made by the French Champagne house Taittinger.
Vintage port from 1977 and Champagne Cognac from 1948 were selected to reflect the respective birthdays of the President and the King.
The royal household’s resident mixologist had created a cocktail called L’entente, which combined British gin with lemon curd and French pastis and was garnished with dried French cornflowers and English roses.
The tables were decked with hand-picked, seasonal flowers, including stocks, hydrangea, lavender, roses and herbs, all arranged in silver‑gilt centrepieces taken from the Grand Service.
Music from the Duchess of Edinburgh's String Orchestra included a nod to France with pieces by Saint-Saëns, Bizet, Debussy and even Daft Punk.
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