The couple are in the process of divorcing, and will share custody of their two daughters.
A spokesperson for the pair, who wed at St George’s Chapel in Windsor Castle in 2008, said the decision was taken after many months of discussion, and they informed the Queen and their families last year.
Canadian-born Autumn will not return to her home country, but will remain in Gloucestershire where they will co-parent nine-year-old Savannah and seven-year-old Isla.
The spokesperson said: “They had reached the conclusion that this was the best course of action for their two children and ongoing friendship.
“The decision to divorce and share custody came about after many months of discussions and, although sad, is an amicable one.
“The couple’s first priority will remain the continued well-being and upbringing of their wonderful daughters, Savannah and Isla.
“Both families were naturally sad at the announcement, but fully supportive of Peter and Autumn in the joint decision to co-parent their children.”
“Both Peter and Autumn have remained in Gloucestershire to bring up their two children where they have been settled for a number of years.”
The couple requested “privacy and compassion” for their children while the family continues to adapt to the changes.