Kate Middleton, Prince William, family
Kate Middleton, Prince William, Prince Louis, Princess Charlotte and Prince George
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Kate Middleton and Prince William may have to change their Christmas plans after strict COVID-19 restrictions have been put in place for much of England due to an infectious new coronavirus strain in the U.K.

After it was announced that Queen Elizabeth had canceled the royal family's annual holiday celebration at her Sandringham estate, it was speculated that Kate, William and their three kids — Prince George, 7, Princess Charlotte, 5, and Prince Louis, 2 — would ring in the holiday with Kate's family in Bucklebury, Berkshire.

But Berkshire, where Mike and Carole Middleton live, and London, where Kate's sister Pippa Middleton and husband James Matthews live, have now been placed into Tier 4 lockdown, which bans all households from mixing and overnight stays away from home. A travel ban has also been introduced, with no exit or entry from the Tier 4 regions.

It would have marked the first time in recent years that the entire Middleton family would be celebrating Christmas together as William and Kate have spent the past few holidays with the royal family.

The Duke and Duchess Of Cambridge And Their Family Attend Special Pantomime Performance To Thank Key Workers
Prince William and Kate Middleton take their kids to the theater
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William, Kate and the kids have spent much of the pandemic at their country home, Amner Hall, in Norfolk, and it is thought that they'll remain there for the holidays. Norfolk is in Tier 2, which means they can entertain two other households, just on Christmas Day, but those people need to live within Tier 2 regions as well.

Earlier this month, William opened up about his family's frustrations over how they'll spend the holidays.

"It is so difficult. We are still trying to make plans," he said. "It's difficult to know what to do for the best."

royals Windsor
Kate Middleton, Prince William and Queen Elizabeth
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Queen Elizabeth, 94, called off her regular trip to Sandringham for Christmas. Instead, she and husband Prince Philip, 99, will stay at Windsor Castle, where they have spent much of their time in quarantine since March.

A royal source told PEOPLE, "They are fortunate to spend Christmas with their family every year, but they understand that their family will have competing demands over the Christmas period and are content to have a quiet festive season this year."