A former aide of Prince William has revealed how difficult it was for the first-in-line to the throne when he found out his wife Princess Kate had cancer last year.

After a planned abdominal surgery at the start of last year, the Princess of Wales, 43, then received a cancer diagnosis shortly afterwards.

While Prince William, 42, has since spoken out about his wife’s cancer, calling last year “brutal”, he has never revealed how he really felt in the moment when the diagnosis was first made.

Now the princess has finished chemotherapy and is in remission, a former aide of the couple has revealed how William really coped with the diagnosis.

In an interview with 60 Minutes Australia for a documentary called Where There’s a Will, Jason Knauf, a former chief executive of the Prince and Princess of Wales’ Royal Foundation, described the prince’s reaction to his wife’s cancer in a heartbreaking six-word remark.

Knauf, who also once worked for the Duke and Duchess of Sussex, said the prince was the “lowest I have ever seen him”.