One day before the State Opening of British Parliament is set to take place, Queen Elizabeth II has pulled out.

The monarch’s decision was made today and is due to her ongoing mobility issues, which she has been experiencing since last fall.

“The Queen continues to experience episodic mobility problems, and in consultation with her doctors has reluctantly decided that she will not attend the State Opening of Parliament tomorrow,” a palace source tells

“At Her Majesty’s request, and with the agreement of the relevant authorities,” Charles, Prince of Wales, and Prince William, Duke of Cambridge, will take her place and jointly exercise the function, the source said. Camilla, Duchess of Cornwall, will also be present at the event, as was originally planned.

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Despite her absence from tomorrow’s outing (the first time she’ll miss the event in nearly 60 years), the queen, 96, has a busy week ahead. Today, she had a call with Australia, and on Wednesday, she has a planned Privy Council engagement and an audience with British Prime Minister Boris Johnson, as well as other private engagements in the following days.

The queen has been having some health issues in the past several months, mostly relating to her mobility, and has, therefore, been taking most of her audiences virtually and by phone, rather than in person.

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This February, she also tested positive for COVID-19, but recovered quite quickly and was back on her feet soon enough.

In March, she decided not to attend the Commonwealth Day church service and left the spotlight to Prince William and Duchess Kate instead. The queen watched a live broadcast of the service from her Windsor Castle home.

Royal sources told BAZAAR at the time that the monarch’s decision came with “regrets,” but followed private discussions surrounding her comfort to travel over an hour from Windsor Castle to Westminster Abbey for the service.

She is set to attend Platinum Jubilee celebrations—including the traditional Trooping the Colour balcony appearance—with her close family on June 2.

This article originally appeared on Harper’s BAZAAR US.

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