Prince Harry and Meghan Markle have stopped holding hands in public, and there may be an important why they did.

Last week, the Duke and Duchess of Sussex joined Queen Elizabeth II at the Queen's Young Leaders Awards ceremony. Many noticed that Markle tried to reach out and hold her husband's hand, but Prince Harry ignored her effort and instead brought his arms together.

According to etiquette expert William Hanson, it is possible there is no need for Prince Harry to hold his wife's hand in public as Markle is now more confident. In addition, not holding hands makes them appear more professional.

"Prince Harry has probably felt less of a need to hold Meghan's hand as she seems to be much more confident and secure in her new role, and so needs less emotional and physical support from her now-husband," Hanson told Femail.

"Public displays of affection, such a hand holding, may be accepted in private situations and in social spheres, but when out in public Harry and Meghan are on official business and so it is not considered professional behaviour," the expert continued.

According to Hanson, Prince William and Kate Middleton's body language is more "traditional." The Duke and Duchess of Cambridge are reportedly "more reserved" when it comes to their emotions and affection compared to the Duke and Duchess of Sussex who are tactile people.

Meanwhile, according to People, Prince Harry "knows the drills when his grandmother, the Queen is around." As a result, he declined to hold hands with his wife.

Queen Elizabeth II and Prince Philip never showed PDA despite their closeness. According to royal biographer Gyles Brandreth, this could be due to the "stoic values" of their generation.

"The Queen rarely holds hands with her husband in public and this seems to have set an unwritten precedent for the other royals," Robin Kermode explained. "It is very clear that William and Kate are emotionally close, however, they do not seem to feel the need to prove their love – particularly when on official state business."

Prince Harry and Markle have never been shy when it comes to displaying PDA. In fact, when they made their first public appearance as a couple, they were photographed holding hands. They continued to do so in a number of royal engagements they attended together, but didn't act the same in the presence of the Queen.

Prince Harry and Meghan Markle Prince Harry and Meghan Markle have stopped holding hands for this reason, according to a royal expert. Pictured: Prince Harry and Markle visit Reprezent 107.3FM on January 9, 2018 in London. Photo: Getty Images/Chris Jackson