The King has spoken movingly about his mother’s ties to France as he told of the “firm friendship” between the nations at a state banquet in Paris.
Charles and Queen Camilla were guests of honour at a black tie dinner hosted by French President Emmanuel Macron in the Palace of Versailles’ Hall of Mirrors.
The royal couple are visiting Paris and Bordeaux, six months after the trip had to be rescheduled because of widespread rioting across France.
High-profile figures invited to the dinner to mark their “contribution to UK-France relations”, including Rolling Stones frontman Sir Mick Jagger and actor Hugh Grant, were among the 160 guests addressed by Charles and Mr Macron on Wednesday evening.
The King told the president: “Your generosity of spirit brings to mind how my family and I were so greatly moved by the tributes paid in France to my mother, the late Queen, whose funeral took place one year ago yesterday.
“Mr President, among the many profoundly moving gestures here, the flying of the Union flag at the Elysee was particularly poignant.
“Your words, at that time, meant a great dealt to us too. You said that she had touched your hearts - and it was she who held France in the greatest affection, as, of course, did my grandmother Queen Elizabeth, the Queen Mother.
“My parents’ first official visit together was to France in 1948, shortly after their wedding.
“By all accounts, they made quite a splash, dancing till the early hours at the glamourous Chez Carrere in the Rue Pierre Charron, serenaded by Edith Piaf.
“I suspect it may have left an indelible impression on me, even six months before I was born - La Vie En Rose is one of my favourite songs to this day.”
The King also said relations between the UK and France have not always been “straightforward”, but went on to stress the unity between the nations.
Charles also mentioned the importance of Britain working with France to tackle climate change.
He went on: “Mr President, in all of this we can rely on our firm friendship, which is renewed and reinvigorated with each new generation.
“I would like, if you would allow me, to raise a toast to President and Madame Macron and to the French people, as well as to our entente cordiale - a sustainable alliance.
“Whatever lies ahead, may it endure, faithful and constant, for centuries to come.”
Well-known faces of English football, including former Arsenal manager Arsene Wenger, ex-Chelsea striker Didier Drogba and Patrick Vieira, who played for Arsenal and managed Crystal Palace, were also in attendance.
Guests dined on lobster, Bresse chicken and cheese.
Camilla dazzled in a midnight blue silk crepe dress and matching cape by Dior, and wore sapphire and diamonds inherited from the late Queen.
Earlier Charles gave Mr Macron a book containing photographs of the pair together, as well as a complete edition of French philosopher Voltaire’s writings, when he visited the Elysee Palace, the president’s official residence.
In return, Mr Macron gave the King a golden coin featuring Charles’s portrait, as well as a prize-winning French novel.
The pair arrived at the Elysee together by car, closely followed by the Queen and the president’s wife Brigitte Macron.
They later planted an oak tree, also a gift from Mr Macron.
During the earlier event, Camilla wore a dusky pink, wool crepe coat-dress by Fiona Clare, and a pink beret-style hat by milliner Philip Treacy.
The couple had landed at Paris Orly airport, where they were greeted with a guard of honour from the Republican Guard, which is part of the French National Gendarmerie.
They then attended a ceremony of remembrance and wreath-laying at the Arc de Triomphe in the centre of the capital.
Charles symbolically lit the monument’s eternal flame, which burns in memory of those who died in the First and Second World Wars.
It was the first time in 30 years the ceremony has been included in a state visit.
The French and British national anthems were played and there was a flypast by the Patrouille de France and Red Arrows before the couples travelled down the Champs Elysees by car.
The majority of the original royal programme has been retained but a few new elements have been added, including the Queen and Mrs Macron launching a new Franco-British literary prize at the Bibliotheque Nationale de France.
Charles will become the first British monarch to give a speech from France’s senate chamber on Thursday.
Other highlights include the royal couple meeting sports stars as France hosts the Rugby World Cup.
When the couple travel to Bordeaux, home to 39,000 Britons, they will meet UK and French military personnel to hear about how the two nations are collaborating on defence.
The planned tour in March was to be their first state visit, but it was postponed at the last minute after violent nationwide demonstrations by those opposed to Mr Macron’s retirement age reforms.
Bordeaux’s town hall was set on fire by protesters just a few days before the trip was due to begin.
