Piers – who recorded his interview with Oprah in California earlier this week - said: “She’s a compelling interview.
“Everyone has interviewed Oprah over the years. Is my interview as good as the ones that have been done before? She thought so.
“I guarantee you’ll enjoy this one.”
The former ‘Britain’s Got Talent’ judge – who was reportedly handed an $8.4million deal to front the programme – insisted he only ever had Oprah in mind to be his first guest on the show, which begins on January 17.
He added in a video interview on the show’s official website: “So I was determined to start my new show with the ultimate bang and for that I needed the biggest star in the world but also somebody who was one of the most powerful people in the world.
“And that narrowed the list down as far I as I was concerned, to one person.”
However, 56-year-old Oprah – who is sitting next to Piers in the clip – jokingly interrupted his praise to say: “And that person wasn't available... so he got me.”