King Charles was deeply affected by Prince Harry's decision to step back from his duties and move to the US with Meghan Markle, a new book has revealed.

Royal expert Robert Jobson talked of the monarch’s heartbreak after his ‘darling’ boy Harry revealed he no longer wanted to be a part of the Royal family.

Writing in Catherine, the Princess of Wales, Jobson shared the deep bond Charles shared with the Duke of Sussex and how much efforts he put in welcoming Meghan into the Royal family.

"At first Charles tried to reach out to Meghan and treated her with the same love and affection as he did Catherine. But they are very different characters,” he wrote in his new book, as reported by The Express.

"He welcomed her with open arms and wanted her to feel part of the family. That is why Harry and Meghan's behaviour has cut him to the quick,” the author added.

However, following their exit, King Charles grew close to the heir of the throne, Prince William. "Before all this happened, Charles was much closer to his second son than to William,” Jobson said.

"But if there is a positive to be taken from the Sussexes' departure, it is that William and his father are now closer than they were before, perhaps more than they have ever been."