Meghan and her fiance Harry, 33, are expected to join other members of the Royal Family, including the Queen and the Duke of Edinburgh, the Duke and Duchess of Cambridge and Prince Charles and Camilla, for a Christmas Eve black-tie dinner.

They will also have a full English breakfast on Christmas morning before going to church and a pheasant shoot on Boxing Day.

They will be at the Norfolk estate from Christmas Eve until Boxing Day, it is believed. She will also become the first royal fiancee to open presents with the Queen before becoming a member of the family.

Sources suggested Prince Harry asked the Queen to make an exception so Meghan could join them at Sandringham for the festive period.

Kate Middleton was not invited to the Norfolk estate after she got engaged to Prince William in November 2010.

She spent that Christmas with her parents in their family home in Bucklebury, Berkshire.

A friend of Harry’s said: “Now they are engaged it was unthinkable they would be apart for Christmas.

“The Royal Family have fully welcomed Meghan into the fold.”

Royal commentator Richard Fitzwilliams said: “It is expected Meghan will join Harry and the rest of the family for Christmas on the Queen’s estate in Sandringham in Norfolk this year.

“Now they are engaged and she will shortly be a senior member of the royal family, it is pivotal that she feels an integral part of it as soon as possible.

“Kate and the younger members will help her through the strict protocol of the royal festive celebrations which take place over three days and which can be daunting.”

A source said last week: “Kate was a bag of nerves the first time she did Christmas with the Royals, so she knows exactly how daunting it must be for Meghan.”

Harry and Meghan are understood to be planning to stay with the Duke and Duchess of Cambridge and their two children, George and Charlotte, at Anmer Hall on the Sandringham Estate.

Harry and Meghan are also said to be planning a holiday in the New Year and may travel to California to see Meghan’s mother Doria Radlan.

Kensington Palace has confirmed Meghan plans to visit friends and family in America before settling down with Harry in Nottingham Cottage at Kensington Palace.

The American actress, 36, delighted crowds as she appeared alongside Harry for their first official public engagement together in Nottingham on Friday.