Prince Philip, husband of Queen Elizabeth II, was hospitalized Monday with a bladder infection and will miss the rest of the celebrations of the monarch's 60 years on the throne, Buckingham Palace said.
The palace said the prince, who will turn 91 on Saturday, was taken to the King Edward VII Hospital in London from Windsor Castle as a precaution and will remain under observation for a few days.
He will miss Monday evening's Buckingham Palace pop concert celebrating the queen's jubilee, as well as a service of thanksgiving at St. Paul's Cathedral and a carriage procession Tuesday.
"He is, understandably, disappointed about missing this evening's Diamond Jubilee Concert and tomorrow's engagements," the palace said in a statement.
The palace said the queen would still attend the concert, which will feature performances by Paul McCartney, Elton John and Stevie Wonder.
On Sunday, Prince Philip joined the queen and senior royals on the River Thames in cold, blustery weather for a pageant in honor of Elizabeth's reign.
Philip, who is also known as the Duke of Edinburgh, is a former naval officer who married the queen in 1947. His health remained robust through his 80s, but he has appeared frailer in recent years.
When he turned 90, he said he was "winding down," and he has cut back on official duties. But he still carries out engagements, both with his wife and on his own.
The prince spent four nights in the hospital over Christmas after suffering chest pains and underwent a successful coronary stent procedure.