The 90-year-old Duke of Edinburgh was taken to King Edward VII hospital in Windsor as a "precautionary measure" after developing a bladder infection, Buckingham Palace has confirmed.
The condition is not thought to be serious although it means Philip will miss the remaining events planned to celebrate his wife Queen Elizabeth's Diamond Jubilee.
A series of tweets on the British Monarchy's official account stated: "The Duke of Edinburgh will not attend tonight's Diamond Jubilee.He has been admitted to hospital as a precautionary measure after developing a bladder infection."
Representatives from the palace have revealed he will be kept in for several days for observation.
They added that the duke is disappointed to miss tonight's jubilee concert where acts from the queen's 60-year reign will perform but the monarch will still attend.
Philip will also miss tomorrow's Service of Thanksgiving.
Yesterday, the duke accompanied his wife and other members of the royal family as they travelled on board the luxury Spirit of Chartwell barge as part of the Thames River Pageant.
Despite the poor weather including wind and rain, Philip and Queen Elizabeth were standing for several hours, only taking a brief ten minute respite from the weather when they went downstairs.