President Emmanuel Macron winked at Catherine, Princess of Wales when they met at Windsor Castle

An image of Macron winking at Catherine, 43, quickly went viral on social media, as he and her father-in-law King Charles pulled out her seat and waited for her to sit down as an act of courtesy.

Several users on platforms such as X, TikTok and Instagram even questioned whether the suggestive move would land Macon - who has been married to Brigitte Macron, 72, since 2017 - in hot water with his wife.

According to the Royal Family's website, there is no strict code of conduct when it comes to meeting a member.

It states: "There are no obligatory codes of behaviour when meeting The Queen or a member of the Royal Family, but many people wish to observe the traditional forms. For men, this is a neck bow (from the head only) whilst women do a small curtsy. Other people prefer simply to shake hands in the usual way."

The banquet's seating plan was arranged with each member sitting opposite their spouse, so that King Charles, 76, was opposite Queen Camilla, Macron and Kate were seated together on one side, Prince William, 43, sat next to Macron's wife.

UK Prime Minister Sir Keir Starmer was also in attendance, alongside several A-Listers such as Rolling Stones rocker Sir Mick Jagger, pop legend Sir Elton John, his husband David Furnish and Slow Horses actress Kristin Scott-Thomas.

At one point during the banquet, the monarch quipped that his visitors had enjoyed an English sparkling wine that was produced by a French champage house, in a move he claimed would have been "scarcely believable" to those in years gone by.

He said: "This evening, we have drunk English sparkling wine made by a French champagne house. This would have been scarcely believable to at least some of our predecessors."

Meanwhile, when Macron addressed the party, he insisted on pointing out the bond between the two European countries.

He said: "On either side of the Channel, there is a constant reminder that we must never lower our guard."