▶ Watch Video: Prince Harry opens up about Princess Diana in CBS interview with Oprah London — In an interview recorded weeks ago, Meghan, Duchess of Sussex, accuses Britain’s royal family of actively encouraging lies about her, raising tensions to another level ahead of Oprah Winfrey’s interview with her and Prince Harry that is set to air on Sunday. Meghan’s allegation came out following published claims that she mistreated royal staffers, which Buckingham Palace says it is investigating. As CBS News senior foreign correspondent Elizabeth Palmer reports, it’s not only a fight between family members, it’s a battle over the royal brand. Asked by Oprah in the soon-to-broadcast interview how she feels about the palace hearing her speaking out about life in the royal bubble, Meghan said she didn’t “know how they could expect that, after all of this time, we would still just be silent if there is an active role that ‘The Firm’ is playing in perpetuating falsehoods about us.” Harry and Meghan sit down with Oprah 01:47 In the interview recorded two weeks ago, Meghan uses a common nickname for the royal family in Britain. Right now at “The Firm,” behind all the polished smiles, the gloves are off. “You could probably only describe that relationship now, between the two sides, as all-out war,” Sunday Times royal correspondent Roya Nikkhah told CBS News. CBS News has confirmed allegations first reported on Wednesday by The London Times that after Meghan Markle married Prince Harry in 2018 and moved into the royal household, she bullied staff. Unnamed staffers accused her of using “emotional cruelty and manipulation,” and forcing two aides to quit. In a rare move, Buckingham Palace issued a public response, saying it was “clearly very concerned about allegations in The Times,” and that its human resources team “will look into the circumstances outlined in the article.” So why would the palace chose to break with its custom of silence on virtually all contentious matters? “I think the feeling is, it can’t be right for the Duke and Duchess of Sussex to sit down for two hours with Oprah and say their piece, and to not have the people who worked with them, dealt with them and who know them, also say their piece,” said Nikkhah. Meghan and Harry have called the allegations against the Duchess a calculated smear campaign. Prince Harry sips tea with James Corden 03:51 It’s a new low point in Harry’s relationship with his family, but also with the British media — something he discussed with James Corden on the “Late, Late Show” last week. “We all know what the British press can be like, and it was destroying my mental health… I was like, ‘This is toxic,'” the prince told Corden. “So I did what any husband and what any father would do — was like, ‘I need to get my family out of here.'” The timing of all this couldn’t be worse for the royal family. Queen Elizabeth II’s husband Prince Philip, Prince Harry’s grandfather — who is just three months shy of his 100th birthday — has been hospitalized for two weeks and just had surgery for long-standing problems with his heart.