Queen Elizabeth spent Wednesday night in hospital, Buckingham Palace says

Queen Elizabeth spent the night inhospital after cancelling an official trip to Northern Ireland earlier this week on medical advice, Buckingham Palace said Thursday.

The palace said the 95-year-old monarch went to the private King Edward VII's Hospital in London on Wednesday for "preliminary investigations."

It said she returned to her Windsor Castle home at lunchtime on Thursday, "and remains in good spirits."

On Wednesday, the Queen cancelled a scheduled trip to mark 100 years since the creation of Northern Ireland, and the palace said she had "reluctantly" accepted medical advice to rest for a few days.

It did not elaborate, but the decision was understood not to be related to COVID-19. The Queen has been vaccinated against the coronavirus.

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The Queen's message stressed the importance of community, even at a distance, during the pandemic and how international solidarity will be key to a prosperous future.

The palace confirmed the Queen's hospital stay after The Sun newspaper reported the news.

She is now at Windsor Castle, west of London, where she has spent much of her time since the onset of the COVID-19 pandemic last year.

The decision came just days after the Queenwas seen using a walking stick at a major public event when attending a Westminster Abbey service marking the centenary of the Royal British Legion, an armed forces charity.

She had previously been photographed using a cane in 2003, but that was after she underwent knee surgery.

Active workload

Britain's longest-lived and longest-reigning monarch, Elizabeth is due to celebrate her Platinum Jubilee 70 years on the throne next year.

Elizabeth has ruled since 1952 and was widowed this year when Prince Philip died at age 99 in April.

On Tuesday, she held audiences with diplomats and hosted a reception at Windsor Castle for global business leaders,and on Saturday the equine aficionado attended horse racing at Ascot Racecourse.

In less than two weeks she is due to host world leaders at the United Nations climate summit in Glasgow, Scotland.

She has generally enjoyed good health throughout her long life. She was last hospitalized in 2013, when she was 86, after experiencing symptoms of gastroenteritis.

She recently declined the honour of being named "Oldie of the Year" by The Oldie magazine. Her office said that "Her Majesty believes you are as old as you feel, as such The Queen does not believe she meets the relevant criteria to be able to accept."