Prince Philip, Queen Elizabeth II's 96-year-old husband, pulled out of an annual pre-Easter church service on Thursday because of a hip problem, Reuters reported.
Philip, aka the Duke of Edinburgh, was due to make a rare public appearance at the Royal Maundy Service, which took place at St. George's Chapel at Windsor Castle, and then attend a reception and lunch. His 91-year-old wife attended the event without him.
"The duke was keen to attend but made this decision because he has been experiencing some trouble with his hip," the royal source told Reuters.
"The Order of Service was printed some weeks ago when it was hoped the Duke would be able to take part," a Buckingham Palace spokesperson told E! News. "His Royal Highness has since decided not to attend."
Philip retired from public life last summer. At the time, Buckingham Palace said that "the Duke will not be accepting new invitations for visits and engagements, although he may still choose to attend certain public events from time to time."
Last week, it was reported that Philip had canceled an appearance at a Windsor Castle ceremony, in which he would formally hand over his role as Colonel of the Grenadier Guards to his son Prince Andrew, because he was feeling under the weather. His illness was not thought to be serious. Buckingham Palace did not comment.
Last June, Philip was hospitalized "as a precautionary measure" to treat an infection "arising from a pre-existing condition."
Maundy Thursday commemorates the last supper of Jesus Christ and marks the beginning of the three day Easter holiday celebration. During the traditional Maundy service, the queen hands out money to 91 male and 91 female pensioners in the local community.
St George's Chapel is where the wedding ceremony of Prince Harry and Meghan Markle will take place on May 19.
—Reporting by Holly Passalaqua