Prince Philip, 98, Hospitalized Just Ahead of Christmas Due to 'Pre-Existing Condition'

Buckingham Palace confirmed that Queen Elizabeth's husband traveled from Norfolk to a London hospital on Friday morning

Prince Philip has been hospitalized, the palace has confirmed on Friday.

“The Duke of Edinburgh travelled from Norfolk this morning to the King Edward VII Hospital in London for observation and treatment in relation to a pre-existing condition,” Buckingham Palace said in a statement. “The admission is a precautionary measure, on the advice of His Royal Highness’ Doctor.”

A royal source tells PEOPLE that Prince Philip did not travel by ambulance.

“It was a planned admission, and he walked into the hospital unaided,” the source added.

Meanwhile, Queen Elizabeth took her annual train ride from London to Norfolk, where she traditionally spends Christmas. It’s unclear how long her husband will stay in the hospital — and if he’ll miss Christmas with the family.

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Queen Elizabeth’s husband — who retired from his public duties in August 2017 — has been plagued by health issues in recent years. He abruptly cancelled his appearance at the traditional Maundy church service that he was scheduled to attend with the monarch in March 2018. Philip also skipped Easter Sunday services last year ahead of the announcement that he underwent hip replacement surgery.

However, the Duke of Edinburgh has been seen in public multiple times in the past year, often driving his car (despite a scary car accident in January that resulted in him voluntarily giving up his license) or on carriage rides on grounds of Windsor.

He has also been absent from Trooping the Colour celebrations since his retirement. But the royal was in attendance at Prince Harry’s nuptials to Meghan Markle in May 2018. He also attended his granddaughter Princess Eugenie’s royal wedding in October 2018.

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Prince Philipreportedly involved in talks recently with his son Prince Andrew amid the ongoing fallout from the disastrous Nov. 16 interview regarding Andrew’s relationship with Jeffrey Epstein. A family meeting, which Prince Charles also attended, took place at Sandringham, where Philip has been staying at the estate’s Wood farm.

Last month, Philip and Queen Elizabeth also marked their 72nd wedding anniversary. However, they spent the day apart, as the 93-year-old monarch undertook solo duties in London.