Britain's Prince Philip has been admitted to the hospital for an exploratory operation related to an unspecified abdominal ailment.
Buckingham Palace announced that the 91-year-old Duke of Edinburgh -- who has been absent from several high-profile royal events beginning in May -- was admitted to the London Clinic and will undergo the operation on Friday under general anesthesia. He is expected to remain in the hospital for up to two weeks.
Prince Philip pulled out of an event earlier this week due to illness and The Palace said he had undergone "abdominal investigations," but did not elaborate further. He later attended a service marking the 60th anniversary of his wife Queen Elizabeth's coronation.
The Duke of Edinburgh spent almost a week in the hospital last summer after the recurrence of a bladder infection.