Prince William sparks frenzy with sweet and rare public gesture towards Princess Kate

The Prince of Wales sparked an online frenzy as he was spotted lovingly placing an arm on his wife's back on her first major royal engagement in a month.

and have been careful in following and Prince Philip's example when out in public, refraining from displaying their affection for one another on most occasions.

However, the Prince and Princess of Wales shared several "affectionate touch rituals" as they .

One such gesture was spotted by a royal fan outside the prestigious London venue.

The royal fan, with the X handle @crowningred, shared a video on social media showing William affectionately placing his hand on Kate's back or his arm around her.

They commented on the clip saying: "The Prince and Princess of Wales are at The Royal Albert Hall! Love William constantly putting his arm around Catherine."

This public display of affection prompted other royal fans to express their delight, with one saying: "It's very clear she is precious to him."

Another wrote: "Aww it warms my heart. Prince William is protective of her."

And yet another said: "How I missed seeing our favourite love birds together again."

Commenting on Kate's public appearance and her interactions with William, body language guru Judi James told the : "Her arrival with William showed some stunning body language signs of a change for them as a couple too.

"In the few steps it took to leave the car and greet their hosts it was almost possible to lose count of the affectionate touch rituals and glances exchanged between them."

Ms James said the royal couple seemed to be "compelled to keep touching each other in a behaviour you often normally see from couples newly in love".

She explained: "William places an arm round Kate's back and she reciprocates by leaning back closer to him and putting a hand around his waist, suggesting mutual support and affection.

"William responds with three more touches or virtual hugs, almost as though he can't bear to take his hands off Kate or let her go, during one of her first appearances back in public."

The Festival of Remembrance marked Kate's first public engagement since her .

Today, the Princess of Wales will be among the highest-ranking royals attending the National Service of Remembrance at the Cenotaph in central London.