Video report by ITV News Royal Editor Chris Ship
Meghan has revealed how she finds it "really liberating" to be able to speak for herself, without other people making choices for her.
In the latest clip ahead of the billed 'tell-all' interview with Oprah Winfrey, the duchess recalls how she turned down an interview with the US chat show hot in February or March 2018, before the royal wedding.
Meghan said: "I wasn't even allowed to have that conversation with you personally. There had to be (other people) sitting there."
In the clip, Oprah then asks her why now is the right time to have an interview.
ITV News Royal Editor Chris Ship analyses the latest preview clip of Meghan and Harry's interview with Oprah Winfrey:
Meghan says: "So many things - that we're on the other side of a lot of life experience that's happened and also that we have the ability to make our own choices in a way that I couldn't have said yes to you then. That wasn't my choice to make."
She continued: "As an adult who lived a really independent life to then go into this construct that is different than I think what people imagine it to be, it's really liberating to have the right and the privilege to be able to say yes, and I'm ready to talk.
"To be able to just make a choice on your own, and just be able to speak for yourself."
It is the couple's first interview of its kind since they left the UK and they are expected to speak about their decision to step back from the Royal Family.
In other preview clips released by CBS, Meghan suggested the Royal Family played an "active part" in “perpetuating falsehoods" about the couple, while Harry said he feared "history repeating itself" - comparing Meghan and Diana.
It is alleged in the newspaper that Meghan “drove two personal assistants out of the household and was undermining the confidence of a third staff member”.
Buckingham Palace has said it will investigate the allegations of bullying made against the Duchess of Sussex.
A spokesperson for Harry and Meghan said said the duchess was "saddened by this latest attack on her character", saying she has been the target of bullying herself and supports those who have experienced this pain.
Meghan's friends and colleagues in the US have posted online to counter the claims.
Actor Janina Gavankar wrote: "Here's what she is: 'kind, strong, open'. Here's what she's not: 'A bully'."
While former co-star Patrick J Adams wrote: "Find someone else to admonish, berate and torment. My friend Meghan is way out of your league."
'Perpetuating falsehoods about us'
In the 30-second clip released on Thursday, Oprah asks the duchess: “How do you feel about the Palace hearing you speak your truth today?”
She replies: “I don’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.
“And, if that comes with risk of losing things, I mean, I … there is a lot that has been lost already.”
'My biggest concern was history repeating itself'
CBS released two other preview clips on Monday. The first video begins with Oprah asking the Duchess of Sussex if she was “silent or silenced”, with Meghan’s answer not revealed.
She then asks the duchess: “Almost unsurvivable. Sounds like there was a breaking point?” The clip then cuts to the duke commenting: “My biggest concern was history repeating itself.”
In the second video, Harry says: "“I’m just really relieved and happy to be sitting here, talking to you, with my wife by my side, because I can’t begin to imagine what it must have been like for her, going through this process by herself, all those years ago.
“Because it has been unbelievably tough for the two of us, but at least we had each other.”
Harry also appeared on US talk show The Late Late Show on February 26, where he told host James Cordon about the "toxic" atmosphere created by the British press.
Oprah With Meghan and Harry will be broadcast in the UK on ITV on Monday 8 March at 9pm. It will also be available on ITV Hub.
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