The Duke of Edinburgh has been taken to hospital 'as a precautionary measure', Buckingham Palace said.

The Duke of Edinburgh has been taken to hospital 'as a precautionary measure', Buckingham Palace said.

Prince Philip, 91, was admitted to Aberdeen Royal Infirmary while staying at Balmoral with the Queen, a spokeswoman said.

Details of the reason for his hospitalisation were not available.

It comes two-and-a-half months after he spent five nights in hospital with a bladder infection following the Diamond Jubilee Pageant on the River Thames.

The Duke also suffered a heart scare after he arrived at Sandringham for the Royal Family's traditional Christmas break in Norfolk last December.

He was airlifted to Papworth Hospital, in Cambridge, where he had a stent fitted to a blocked artery.

It meant he missed the Royals' traditional Christmas Day church service, attended by thousands of well-wishers for the first time.

When the Duke was released from Papworth, he was told to rest and reportedly had to give up shooting.

Before the heart problem he had been fit and apparently healthy, and led the active life of a man of much younger years.

In March this year his grandson Prince Harry said the operation had given him 'a new spurt of life'.

But the Duke was forced to miss some of the jubilee celebrations in June after he was admitted to hospital the day after braving the elements for the pageant.

Prince Philip was at the Queen's side during the Opening Ceremony of the London Olympics on July 27 and the following when they toured the Olympic Park.

While in Scotland earlier this month he supported the Queen at engagements including hosting a tea party at Balmoral to mark the end of her Diamond Jubilee celebrations.

A Buckingham Palace spokesman said the Duke travelled to the hospital, about 40 miles away from Balmoral, by road.

He went to Balmoral after attending a number of Olympics events, including granddaughter Zara Phillips' Olympic debut on July 29.

The spokesman added: 'He has been resident at the castle for a short while but whilst he has been there, he has also undertaken engagements on the Isle of Wight.'

The Duke appeared to be in good spirits as he took part in events as part of Cowes Week, in his role as Admiral and member of the Royal Yacht Squadron.

He viewed the racing in the Solent yesterday before attending a luncheon on board a yacht, the My Farragon, accompanied by the Lord-Lieutenant of the Isle of Wight, Major General Martin White.

On Monday, he had been at a luncheon held at Newport's Chamber of Commerce, then visited manufacturers A.J.Wells and Sons in the town before having dinner at the Pavilion in Cowes.