A royal source tells ET, 'The doctor is acting with an abundance of caution.'
Prince Philip is to remain in the hospital, after he was admitted earlier this week.
A royal source tells ET that following a consultation with his doctor, the Duke of Edinburgh "is likely to remain in hospital for observation and rest over the weekend and into next week."
"The doctor is acting with an abundance of caution. The Duke remains in good spirits," the source adds.
The 99-year-old husband of Queen Elizabeth II was hospitalized and taken to the King Edward VII Hospital in London on Tuesday evening. In a statement, Buckingham Palace noted that it was "a precautionary measure" on the advice of his doctor after not feeling well.
At the time, a royal source told ET that he traveled by car to the hospital and was not admitted as an emergency but rather walked into the hospital unaided. The source also asserted Philip's illness is not COVID-19 related. He and the queen received their COVID-19 vaccinations last month, publicly sharing the news to avoid inaccuracies and further speculation.
The news comes the same day that Prince Harry and Meghan Markle confirmed their exit as working members of the royal family, after a year-long trial period.
Buckingham Palace issued a statement on Friday, noting that Harry and his grandmother spoke about the decision.
"The honorary military appointments and royal patronages held by the duke and duchess will therefore be returned to Her Majesty, before being redistributed among working members of the royal family," the statement read. "While all are saddened by their decision, the duke and duchess remain much loved members of the family."
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