The 95-year-old monarch spent a night in the hospital last week and underwent "preliminary investigations" into undisclosed medical issues, though the palace said at the time she was "in good spirits"
Queen Elizabeth
Queen Elizabeth
| Credit: Arthur Edwards - WPA Pool/Getty

Queen Elizabeth will not attend the United Nations COP26 Climate Change Conference in Glasgow, PEOPLE has confirmed.

"Following advice to rest, The Queen has been undertaking light duties at Windsor Castle. Her Majesty has regretfully decided that she will no longer travel to Glasgow to attend the Evening Reception of COP26 on Monday, 1st November," according to a statement from Buckingham Palace. 

The statement continued, "Her Majesty is disappointed not to attend the Reception but will deliver an address to the assembled delegates via a recorded video message."

The news comes just hours after the 95-year-old monarch resumed her royals duties on Tuesday morning with a virtual audience from her home in Windsor. Last Wednesday, the Queen canceled a scheduled trip to Northern Ireland to mark the nation's 100th anniversary after doctors advised her to rest.

The next day, it was revealed that the monarch had stayed overnight in the hospital.

"Following medical advice to rest for a few days, the Queen attended hospital on Wednesday afternoon for some preliminary investigations, returning to Windsor Castle at lunchtime today and remains in good spirits," the palace said in a statement on Thursday.

Queen Elizabeth
Princess Anne and Queen Elizabeth

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Speculation was revived about the well-being Queen — who is Britain's longest-serving monarch at nearly 70 years on the throne — when she and  Princess Anne, 71, attended a Service of Thanksgiving at Westminster Abbey. On that day, the Queen walked with the assistance of a cane for the first time since 2003, when she was recovering from knee surgery.

The Queen had taken back up royal duties following her stay at her beloved Balmoral Castle in Scotland during the summer and early fall.

Prince Charles, 73, and Prince William, 39, are still expected to travel to Glasgow to represent the royals and urge world leaders to join them in confronting the global climate crisis.