Britain's Prince Philip, the 96-year-old husband of Queen Elizabeth, has been admitted to hospital for hip surgery, Buckingham Palace has confirmed.
The Duke of Edinburgh is said to have complained of a problem with his hip which caused him to miss a Windsor Castle event with the Queen last week.
The planned surgery will take place on Wednesday (local time).
"His Royal Highness The Duke of Edinburgh was admitted to King Edward VII Hospital in London this afternoon, for planned surgery on his hip which will take place tomorrow," a spokeswoman said on Tuesday.
The Duke stepped down from his public duties last summer but on occasions does still attend events with the Queen.
When it was announced last year that he would be retiring from official engagements, Buckingham Palace stressed that the decision was not health-related and he had the full support of the Queen.
Prince Philip has suffered from heart disease and other ailments in recent years, but has generally remained in good health.
He and Elizabeth celebrated their 70th wedding anniversary in November.
The Queen has praised her husband for his devotion and long years of service, calling him the rock she depends on.