Piers has long criticised the Duchess of Sussex for her actions while she has been a senior member of the Royal Family, including her relationship with estranged father Thomas Markle.
He wrote: “Ms Markle’s seemingly unlimited thirst for committing attention-seeking acts of gargantuan hypocrisy, this seemed beyond parody.
“I wonder how much these touching sentiments will resonate with her own family, or her husband’s?”
Piers went on to criticise Prince Harry for speaking to Oprah Winfrey while Prince Philip was in hospital.
“He did this as Charles was desperately worried about HIS father, Prince Philip, who was lying seriously ill in hospital and later died,” Piers continued.
Good Morning Britain airs weekdays on ITV at 6am.