It's not every day that the public receives a glimpse of the Prince and Princess of Wales showing their affection for one another.

However, the future king and queen have shared a behind the scenes glimpse from yesterday's glittering state banquet on Instagram where they were holding hands.

Kate and William, both 43, put on dashing displays as they welcomed Donald and Melania Trump for a state banquet at Windsor Castle alongside other senior members of the Royal Family.

Taking to Instagram after the event, the couple, much to the delight of royal fans, shared an image, captioned, 'Behind the scenes', where they held hands as a photographer captured them from behind.

With the exception of their 2011 wedding, the couple rarely exchanged such loving gestures in public in the early days of their marriage.

Now, it seems as though Prince Harry and Meghan Markle's affectionate displays may have rubbed off on the couple, as William has become increasingly comfortable in the spotlight, and isn't afraid to show his public affection for Kate.

The US president and First Lady are currently in the UK undertaking a state visit, and the occasion was marked in style as they joined King Charles, 76, Queen Camilla, 77, Prince William, and Kate at the Windsor Castle event.

Kate looked dazzling, sporting a Phillipa Lepley silk crepe gown underneath a hand-embroidered gold Chantilly lace evening coat. She also donned the late Queen Elizabeth II's and the King's Royal Family Order and a blue sash, representing that she is a Dame Grand Cross of the Royal Victorian Order.

The Prince and Princess of Wales put on dashing displays in formal attire at the Windsor Castle state banquet during U.S. President Donald Trump's state visit yesterday evening

William and Kate held hands in the 'behind the scenes' photograph from Wednesday evening's event

Notably, she also wore the famous Lover's Knot tiara, which was once owned by Princess Diana and was kept in a safe at Buckingham Palace after her 1997 death before it was handed to Kate.

The headpiece - which Diana said was so heavy it gave her headaches - was made by Royal jewellers Garrard in 1914 to Queen Mary's personal design, from pearls and diamonds already in her family's possession.

Prince William's wife wore her newly bronde tresses loose, letting them fall in soft waves underneath her tiara. She accessorised her look with a pair of drop earrings.

Meanwhile, William sported the Windsor Uniform - a dark navy blazer with red collar and cuffs - with with a white shirt, black trousers and the blue sash and star of the Order of the Garter, as well as another star denoting his position as a Knight of the Order of the Thistle, and a third representing that he is a Great Master of the Order of the Bath.

He also wore four medals - one each from the late Queen Elizabeth II's Golden, Diamond and Platinum Jubilees, and the King's coronation medal.

Every element of the banquet was reportedly checked and approved by the King - down to the very last detail.

Charles and the Queen usually inspect the table beforehand in person, making their way round the room in the afternoon and examining the preparations with the Master of the Household, Vice-Admiral Sir Tony Johnstone-Burt.

In a tradition started by the King, a bespoke cocktail was created specially for the occasion.

King Charles and Queen Camilla welcomed the US President and First Lady for the banquet at Windsor Castle yesterday evening

Called Transatlantic Whisky Sour, it was described as a UK/US twist on the classic Whisky Sour, blending Johnnie Walker Black with the bright citrus of marmalade, topped with pecan foam, and garnished with a toasted marshmallow set on a star-shaped biscuit (in reference to a fireside s'more).

President Trump is a teetotaller so it is believed he will not indulge in sampling the variety of vintage wines on offer, nor the cocktail.

Preparations for a state banquet started six months before the big event and it usually takes household staff around three days to lay the table.

Guests - who have been invited on the basis of their cultural, diplomatic or economic links to the US - dined on an exquisite menu, written in French, prepared by royal chefs and served on historic, priceless dinner sets.

Mr Trump's last state visit was in 2019, when he was seated next to then-monarch, the late Queen Elizabeth II in the middle of one side of the table, with Mrs Trump and Camilla opposite them on the other side. Meanwhile, other royals will be spread around the table between the guests.

During that banquet, there were 16 royal family members in attendance. The late Queen Elizabeth II, who hosted the occasion in 2019, died three years ago.

When it came to the meal, royal chef Mark Flanagan and his team of 20 chefs served seasonal produce, sourced from royal estates.

The final menu was selected by Charles and Camilla and features Hampshire watercress panna cotta, organic Norfolk chicken ballotine and vanilla ice bombe with a Kentish raspberry sorbet interior.

The Prince of Wales and the Princess of Wales are seen attending Wednesday's state banquet at Windsor Castle

It's not just the food and drinks that are crucial during an event of this magnitude: the decorations are also key - notably the impressive floral displays, crafted from seasonal flowers handpicked from the gardens at Windsor Castle and Windsor Great Park will.

The blooms were arranged in elaborate displays along the table in silver-gilt centrepieces. After the banquet, the flowers are usually donated to Floral Angels, a charity of which Camilla is patron, which delivers the blooms to hospices, elderly care homes and shelters.

The impressive St George's Hall, where evenings are held, is the largest room in the castle at 55.5 metres long (180ft) and nine metres wide (29.5ft), and the 50 metre (164ft) table stretches its full length.

The hall's gothic style ceiling with impressive oak beam roof is studded with the coats of arms of every single Knight of the Garter since the order was founded in 1348.

State banquets are a huge undertaking for the castle's staff, who would have started constructing the mahogany table almost a week ago.

Tablecloths and napkins - folded in the shape of a Dutch bonnet - cruet sets, elaborate floral decorations, priceless plates, candelabra and six glasses - for water, a champagne toast, red and white wines, a dessert wine and port - will all have carefully been put in order.

Every place setting must be precisely 18 inches apart - with measuring sticks used to ensure absolute precision.

The footmen and women must make sure every chair is exactly the same distance from the table and each glass is the same distance from the front edge of the table.

Pictured: A view of the banquet table in St George's Hall, Windsor Castle, for the state banquet for US President Donald Trump and his wife Melania

Some 19 stations are set up around the edge of the room, each manned by four staff - a page, footman, under butler and a wine butler - who use a traffic light system to co-ordinate the serving of courses.

Detailed diagrams are used to illustrate the serving plans and a list of special instructions sets out any dietary requirements and requests for royals and other guests.

Staff must also put in place a special cushion on the King's seat to ease his long-standing back issues.

In addition, it's been reported that Charles also likes a bowl of olive oil, rather than butter pats, at his setting for his bread.

The dress code is tiaras and white tie - or national dress, with members of the Royal Family wearing sashes and badges known as orders if they have been given them in recognition of royal service.

Earlier yesterday, it was reported that speeches would take place at around 8.30pm when the King and Mr Trump followed their talks by proposing toasts to one another. This was then set to be followed by the playing of the national anthems.

The banquet featured performances by the Duchess of Edinburgh's String Orchestra and The State Trumpeters of the Household Cavalry.

Just before the banquet began, it's understood that members of the royal family lined up to be personally introduced to Mr Trump and First Lady Melania.

Then, the King and Queen and the American couple were formally introduced to, and shook hands with, each and every guest as they filed into the ballroom.

The King and the president then made their way into the room side by side.

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The end of the banquet is signalled by the arrival of 12 pipers processing round the room, a tradition started by Queen Victoria. The pipers from the Scots Guards will play traditional Scottish airs.

Yesterday evening's banquet followed a series of special events following the Trumps' arrival in the UK.

In one of a number of flourishes being added to the American leader's trip, he and wife Melania travelled to Windsor by helicopter, landing on the lawn of the garden nestled in the private Home Park.

William and Kate welcomed the Trumps and walked a short distance with them to meet King Charles III and Queen Camilla outside Victoria House to launch the trip.

Kate was elegant when greeting the US couple, donning an elegant maroon Emilia Wickstead dress, paired with a £2,330 hat by Jane Taylor, and a burgundy Chanel bag that she has carried multiple times before.

Adding a touch of glitz to her ensemble, Kate wore her feather brooch, which once belonged to Princess Diana, studded with 18 round-cut diamonds and small emeralds surrounding the Prince of Wales feathers symbol.

Earlier this week, a Trump spokesperson said the couple was 'thrilled' that Kate would be 'front and centre' during the state visit.

'The inclusion of Princess Kate in so many events during the state visit is an honour.

'The Trumps very much hoped she would be part of their visit but nothing was confirmed until this week because of the princess's health situation.'

Kate is currently in remission from an undisclosed form of cancer as she continues her steady return to public life after receiving treatment.

Kate and William show rare display of PDA at state banquet