"He is a pragmatist and a realist and I'm sure he will accept that while possibly muttering under his breath"

Prince Philip will reluctantly accept that he has to give up driving in public if he is advised to do so following the car crash he was involved in on Thursday, according to friend and biographer Gyles Brandreth.

“He is a pragmatist and a realist and I’m sure he will accept that while possibly muttering under his breath,” Brandreth tells PEOPLE.

But the end of driving on public roads (he would still likely drive around the royal estates) would be “frustrating” for the 97-year-old Duke of Edinburgh. “One of the frustrations of getting older is your world is shrinking. And his life has become more circumscribed,” Brandreth told BBC Radio Four’s Today program Friday.

“He visits old friends but it’s frustrating as you grow older to find your world is getting smaller. The independence for an old person to be able to get into their car and just go down the road is a wonderful thing.”

Royal Family Christmas Lunch at Buckingham Palace, London, UK - 19 Dec 2018
Credit: Tim Rooke/REX/Shutterstock

Asked how the Duke would react to being asked “slow down” in his life, Brandreth – the author of Philip and Elizabeth: A Portrait of a Royal Marriage – said, “I’m not sure he will react too well to that. Everyone will be telling him to slow down – from his wife, to his insurers to the Norfolk constabulary. Knowing him a little, I don’t think he is going to welcome advice to slow down.”

“He is 97 – and still walking without a stick, still carriage driving and still living his life his way. I’m sure this morning, as well as being grateful he’s survived, he will be concerned for the other people involved and shaken by this experience.”

Queen Elizabeth, Prince Philip and Prince Charles
| Credit: OWEN HUMPHREYS/AFP/Getty Images

Philip, who has been staying at the Sandringham estate with Queen Elizabeth, 92, was uninjured in the crash, although those who were on-hand said there was blood at the scene after Philip overturned his Land Rover following a collision with a Kia driven by a 28-year-old woman with a 9-month-old baby in the backseat. Police in Norfolk are investigating.

The scene of the crash
| Credit: MEGA

“He is 98 in June – don’t write him off too soon. He’s a survivor,” Brandreth adds.

He said that when Philip “was younger he was a dynamo” and recalled a conversation he had with Philip’s cousin Countess Mountbatten. She said that her father Lord Mountbatten was once driving with the Queen and Prince Philip though Cowdray Park in Sussex.

“He was going far too fast and the Queen was yelping and drawing in her own breath and flinching,” Brandreth told the radio show. “And Prince Philip turned to her and said, ‘If you do that once more I will put you out of the car!’ When the hair-raising journey came to the end, Lord Mountbatten asked the Queen why she hadn’t protested, saying ‘You’re the Queen.’ But the Queen said ‘You heard what he said and he meant it!’”