In a signed note, Philip says he was “shaken” by the event and was “deeply sorry”.
“I would like you to know how very sorry I am for my part in the accident at the Babingley cross-roads,” the letter reads, according to the Sunday Mirror.
“I have been across that crossing any number of times and I know very well the amount of traffic that uses that main road.
"It was a bright sunny day and at about three in the afternoon, the sun was low over the Wash.
“In other words, the sun was shining low over the main road."
"In normal conditions I would have no difficulty in seeing traffic coming from the Dersingham direction, but I can only imagine that I failed to see the car coming, and I am very contrite about the consequences."
Norfolk Police are continuing their investigation into the crash, which happened on the A149 shortly before 3pm last Thursday near the Queen’s Sandringham estate, when Philip drove his Land Rover Freelander on to the busy A-road.