When Prince Charles greeted Queen Letizia of Spain with a kiss on both cheeks followed by one on the hand this week, many royal watchers noticed and commented on the gesture, with some even concerned that it might have come across as over-familiar.
The much-discussed moment isn't a form of royal greeting that is always seen, with Charles never greeting his daughters-in-law in this way, for example.
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However, kissing the hand of a woman who is higher in rank than himself is a mark of respect, one the heir to the throne often honours when he greets his mother the Queen.
WATCH: Prince Charles welcomes Queen Letizia to Auckland Castle with a sweet kiss
In addition, as eagle-eyed royal observers will notice, the Prince's face only lightly touched Queen Letizia's glove.
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The Queen and her eldest son have been photographed in the pose at many public events over the last few decades as they shared a formal but affectionate greeting.
Prince Charles warmly greeted Queen Letizia
Kissing the Queen's hand has a long history in the UK, and pre-pandemic, new members of the Privy Council were instructed to take the monarch's hand and give it a light kiss.
As The Mirror reports, the Queen's great-great-grandmother Queen Victoria once spoke approvingly of then-prime minister Benjamin Disraeli: "He is full of poetry, romance and chivalry. When he knelt down to kiss my hand, he said 'In loving loyalty and faith'."
The Prince often kisses his mother's hand
Queen Letizia shares a close relationship with the British royal family and appeared delighted to reunite with Prince Charles at Auckland Castle in County Durham Tuesday afternoon, where the pair visited the Francisco de Zurbaran art collection Jacob and His Twelve Sons.
The 49-year-old was a picture of sophistication as she wore a ravishing red dress complete with a black tailored coat, patent heels and a cherry red clutch.
The Spanish royal also visited the UK the previous week in order to attend Prince Philip's memorial at Westminster Abbey.
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