Baroness Brady wrote in her column in The Sun: “It is hard to respect their double standards – worrying about the planet while flying on private jets, calling people racist when Harry’s own past is dotted with misguided moments.
“And now this new chapter, airing all the perceived slights and supposed mistreatment, is totally tone-deaf given the unimaginable levels of privilege they enjoy.
“It is like a soap opera. They have become a problem that will not go away, a weeping sore the Royal Family cannot heal.”
The Duke and Duchess of Sussex resigned from their royal duties in January 2020 and after moving to the US took part in a interview with Oprah Winfrey in which they openly criticised the Royal Family.
They have since signed up to a number of lucrative deals with Netflix, Spotify and now Penguin Random House, with Harry due to publish his own tell-all memoir next year.
Baroness Brady, who sits in The House Of Lords, declared: "They have already caused so much damage. Where will it stop?
"Will there be a reality TV show about their daily lives, like the Kardashians?
"Harry and Meghan appear to have created a new role for themselves as thorns in the Royal Family’s side."
Finding Freedom was first released in hardback last summer and featured numerous revelations about their time as senior royals.
It has now been reissued with fresh chapters covering their explosive Oprah Winfrey interview and Prince Philip's death in April.
The new chapters claim that some members of the Royal Family were “quietly pleased” the Duchess of Sussex was unable to attend the Duke of Edinburgh's funeral because they feared that she would “create a spectacle” if she was present.
Markle gave birth to her second child, a baby girl, in June.
Watch: Harry and Meghan biography Finding Freedom republished with new revelations