Thomas has never met Meghan's husband Prince Harry, nor his grandson Archie. The father-daughter duo fell out after it emerged that the retired lighting director had staged paparazzi photos ahead of the royal wedding.
When asked during an appearance on Oprah With Meghan and Harry: A CBS Primetime Special whether she felt "betrayed" that her father was "working with the tabloids," the Duchess said that Thomas had denied it all. "When I asked him, he said, 'No, absolutely not [that he hadn't been talking to the tabloids],'" Meghan revealed.
WATCH: We debrief Harry and Meghan's explosive interview with Oprah
But when she probed her father further, saying that she and Harry had offered to try and "kill" the news story if he was in fact telling the truth, Thomas wasn't able to say that he was.
"I said, I just need you to tell me and if you tell me the truth we can help. And he wasn't able to do that," said Meghan.
The Duchess, who is pregnant with her second child, also said that as a mother, she couldn't imagine causing Archie the same pain. "I genuinely can't imagine doing anything to intentionally cause pain to my child, so it's hard for me to reconcile that," she said.
Meghan and her father Thomas are estranged
Meghan also opened up about her half-sister, Samantha Markle, admitting that the pair really do not have a relationship. She said it must have been hard for Samantha to write a "tell-all book" about her when she didn't know her at all.
"I grew up as an only child and I wished I had siblings… the last time I saw her must have been 18, 19 years ago, and before that, ten years before that," said Meghan, adding: "She changed her last name back to Markle only when I started dating Harry, so I think that says enough."
The new previously unseen clip from the Oprah interview was aired as a follow-up on CBS This Morning on Monday. Presenters Gayle King, Anthony Mason and Tony Dokoupil interviewed Oprah about the explosive interview, and asked whether she knew if Meghan was open to having a relationship with her father.
The couple spoke to Oprah about the royal family, their son Archie and more
"Her relationship with her father is similar to what's happening between Harry and William," said Oprah. "There's distance there, maybe with time it'll get better, but for now, no."
During the much-anticipated interview that aired on Sunday evening in the US, Meghan spoke about stepping into life as a royal, marriage, motherhood, her philanthropic work and how she is handling life under intense public pressure.
WHERE TO WATCH: In the US, the show was broadcast on Sunday evening on CBS. In the UK, CBS Presents Oprah with Meghan and Harry will be broadcast on Monday night at 9pm on ITV, and on ITV hub.
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