Prince Harry's former aide said that dealing with the Duke and Duchess of Sussex was like "dealing with teenagers", a royal author has claimed.
Samantha Cohen resigned as private secretary to the couple in October 2019, taking up a job with Cool Earth, a charitable organisation dedicated to reducing carbon emissions.
She was later approached by Boris Johnson and became the head of the Prime Minister's office in April this year.
Royal correspondent Valentine Low, who penned the new book 'Courtiers: The Hidden Power Behind the Crown', has now claimed that Ms Cohen was "treated harshly" during her time working for the Sussexes.
Her relationship with Harry is said to have been amicable at the start, but apparently deteriorated as she was "asked to do things a private secretary wouldn't normally be asked to do".
Mr Low told the Mail's Palace Confidential podcast: "When she started, Harry knew her well, and liked her and she liked Harry.
"Sam is an incredible problem solver, she's a can-do personality and she just found it really difficult.
"She was asked to do things that a private secretary wouldn't normally be asked to do and I think she was treated harshly.
"She was shouted at by Meghan… she was said to have said that dealing with them was like dealing with a couple of teenagers."
Ms Cohen revealed in 2018 that she would be leaving her role after working for the royals for almost two decades.
A statement on Cool Earth's website by trustee Mark Ellingham had announced Ms Cohen's appointment.
It said: "Samantha Cohen CVO will be joining Cool Earth as Co-Chair of the Board of Trustees.
"Samantha’s distinguished career ranges from working for the Australian Government to the Royal Household, where she was Assistant Private Secretary to The Queen from 2011-2018, and Head of Royal Communications prior to this."
The statement added: “We are delighted to have Sam Cohen join Cool Earth, after playing such a key role in the creation of the Queens Commonwealth Canopy – an initiative that has done so much to protect forests around the world and to highlight the importance of its preservation and revival."
Ms Cohen was made a Commander of the Royal Victorian Order by the Queen in 2016 having been the first woman to hold the press secretary job.
The communications star rose through the ranks after applying to be a media minder at Buckingham Palace 20 years ago, while on a trip to London from her home country.
Nicknamed 'Samantha the Panther' in royal circles, the Australian also served as a communications secretary during her 17 year career working for the Windsor family.
She is held in high regard by the royal family and had been described as 'unstuffy' and 'deeply committed' to the late Queen.
She had taken on the role as an interim at the request of Harry and Meghan following the departure of predecessor Edward Lane Fox after five years of service, but refused a permanent job.
