Prince Philip marks 92nd birthday in hospital The King's Troop Royal Horse Artillery fire a 41-gun salute in Green Park to mark the 92nd birthday of Prince Philip. Photograph: Facundo Arrizabalaga/EPA The Queen has visited Prince Philip in hospital on his 92nd birthday as he recovers from the exploratory operation on his abdomen. Her arrival at the London Clinic shortly before 7pm on Monday followed a visit from his son Prince Edward earlier in the afternoon. The Earl of Wessex spent less than 20 minutes at the hospital, emerging to say that his father was "well, thank you." In a statement on Monday, Buckingham Palace said: "His Royal Highness the Duke of Edinburgh is progressing according to plans at this early stage. He is comfortable and in good spirits. He will remain in hospital for up to two weeks, and it is expected he will then be taking a period of convalescence of approximately two months. The prime minister, David Cameron, sent a birthday message on Twitter, saying: "Wishing the Duke of Edinburgh a very happy 92nd birthday as he recovers in hospital today." The King's Troop Royal Horse Artillery fired a 41-gun royal salute at midday in Green Park to mark the occasion. This was followed an hour later by a 62-round salvo by the Honourable Artillery Company at the Tower of London. Gun salutes were also fired from Edinburgh Castle in Scotland and Hillsborough Castle in County Down, Northern Ireland. The duke was admitted to the London Clinic on Thursday for the pre-arranged operation, which he had under general anaesthetic. Analysis of the results of the operation are expected to be completed this week.