While making a visit on Monday to South Yorkshire — which was affected by heavy flooding earlier this year — Prince Charles, 71, offered a brief health update to a reporter who asked about his 98-year-old father’s medical condition.
“He’s being looked after very well in hospital,” Charles said. “At the moment that’s all we know.”
“The Duke of Edinburgh traveled from Norfolk this morning to the King Edward VII Hospital in London for observation and treatment in relation to a pre-existing condition,” the palace said in a statement. “The admission is a precautionary measure, on the advice of His Royal Highness’ Doctor.”
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A royal source told PEOPLE that Prince Philip did not travel by ambulance, and that it was a “planned admission, and he walked into the hospital unaided.”
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.
On Saturday, The Telegraph reported that Prince Philip is expected to join his family for the holiday: “Despite increasing fears for the Duke’s health it is hoped he will be discharged and return to Sandringham to join the rest of his family in time for Christmas.”
Prince Philip retired from his public duties in August 2017. (He has also been absent from Trooping the Colour celebrations since his retirement.) In recent years, he has been plagued by health issues.
He abruptly canceled 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.