The Duke of Edinburgh has been taken to Aberdeen Royal Infirmary this afternoon as a "precautionary measure", Buckingham Palace said.
Earlier this week there were social media rumours surrounding Prince Philip's health, before he appeared the start of Cowes week on the Isle of Wight.
The Duke of Edinburgh, 91, spent five days in hospital after the diamond jubilee pageant on the River Thames. On that occasion the prince suffered a bladder infection; he also spent four nights in hospital in Decemember when he received treatment for a blocked coronary artery.
Details of the reason for this hospital visit have not yet been made available.