A statement from Buckingham Palace read: "Following doctor's advice, the Duke of Edinburgh has reluctantly decided not to attend the commemorations marking the Battle of Jutland tomorrow in Kirkwall and Hoy.
Prince Philip has not visited the hospital
"The Princess Royal, who was already attending the events, will represent the Royal Family."
The Prince has not been admitted to hospital, and aides have said he plans to carry out his other upcoming official duties this week.
The Duke of Edinburgh had planned to accompany Princess Anne to attend a service at St Magnus Cathedral and an event at Lyness Royal Naval Cemetery on Hoy to mark the 100 year anniversary of the Battle of Jutland – a naval battle in which over 6,000 Britons and 2,500 Germans lost their lives.
Prince Philip will "reluctantly" miss the event
The 94-year-old, who will turn 95 on 10 June, last had a health scare back in 2012 and has recently seemed to be in good health and very much involved in official duties, including a trip to the zoo in March where he made the zoo keepers laugh with his trademark dry sense of humour, asking them: "You've still got your hands, arms and legs?"
He also told an anecdote regarding a trip to the Gir Forest years ago, saying: "We drove around all day but didn't see a single lion."