Meghan Markle is bringing a "modern approach" to the royal family

He explained: "She's got her own way of doing things ... You look at the energy of Princess Diana and she was very much somebody that would hug people. She was famous for it, wasn't she?"

Historically, the royals - and the Queen, in particular - have not hugged people in public.

But Diana's children, Princes William and Harry, have followed in their mother's footsteps, and so too has Meghan.

Harrold told E! News: "None of the rest of the royal family hugged. It just wasn't the done thing.

"Now the younger royals, Princes William and Harry, you see them hugging ... So it's their way of doing it. They are very much copying what their mother did, which is fantastic."

Despite this, Meghan will have to give up posing for selfies and signing autographs once she becomes a member of the royal family, according to Harrold.

He explained: "She has to be careful what she says, how she says it, and how it's taken because after the 19th of May, it will be very much the reflection of the royal family.

"It's every day things - from the way she walks, the way she speaks, the things she does, how she eats, how she holds her cup, how she dresses - everything will be looked at the right way or the wrong way ... There will be a lot for her to adapt to."

However, once she's married to Prince Harry, Meghan will have the chance to "create the rules" regarding etiquette.

He said: "They do things how they want to adapt them.

"If it's something she does and if the rest of the family lets her do it, it becomes the done thing and that's it."