Prince Harry, Meghan Markle
Prince Harry and Meghan Markle's royal wedding guest rules have been revealed by Grant Harrold. Pictured: Prince Harry, Markle attend a service of commemoration and thanksgiving to mark Anzac Day in Westminster Abbey in London on Apr. 25, 2018. Getty Images/KIRSTY WIGGLESWORTH/AFP

Royal wedding guests are expected to adhere to some strict rules when they attend Prince Harry and Meghan Markle’s wedding on May 19.

Grant Harrold, a royal butler, told Express that all guests are not allowed to use their mobile phones during the ceremony. The use of social media is also prohibited.

“There won’t be any mobile phones, they won’t want anything on Facebook and Twitter, royal weddings are very private,” he said.

No sneaky snaps are to be taken inside St. George’s Chapel in Windsor Castle will also be allowed. But Harrold acknowledged the fact that it would be difficult for the royal staff to control guests from taking pictures so they just hope everyone will be on their best behavior at all times.

Duncan Larcome, a former royal editor, told Cosmopolitan UK that mobile devices need to be put away especially after Queen Elizabeth II arrives at the wedding venue.

“A royal wedding is the only time that the Queen isn’t the last person to walk into a room – she has to wait for the bride. Once the Queen is there, guests will be on their best behavior. Things like tweeting will be an absolute no-no,” he said.

Harrold also said that not all of the guests will have the chance to talk to Prince Harry and Markle on their wedding day.

“With the 600 invitations, the one thing with the guests is it’s not possible for everyone to see the couple and the thing is if you do meet them there’s a lot of people they have to see and you can’t take up all their time,” he said.

Meanwhile, Harrold also said that people should be aware of what to call Markle after she marries Prince Harry.

“Once she’s married to Prince Henry, she will then be Her Royal Highness Princess Henry of Wales because she’s not a princess in her own right, there will probably then be a title. We won’t know her long as Princess Henry because she might be a duchess or a countess so after people meet her at the wedding they have to be aware of that,” he said.