Oprah Winfrey's explosive interview with the Duke and Duchess of Sussex reached an estimated 17.1 million viewers in the United States.

That is according to preliminary numbers from the Nielsen company.

Winfrey guided the two as they discussed racism and dysfunction inside the royal family in a two-hour special on CBS on Sunday.

In the UK demand to watch online was so great that many viewers were left complaining of issues with the ITV Hub site.

Early indications suggest in the UK up to 23 million could have tuned in. 

The live stream of the interview has also been watched almost millions of times. 

More than one million people in Scotland watched the Duke and Duchess of Sussex’s interview with Oprah Winfrey on Monday evening, according to overnight figures.

STV’s audience peaked at 1.1 million during the programme and across the broadcast, which aired between 9pm and 10.50pm, an average audience of 984,000 viewers tuned in to listen to the couple share their story.

READ MORE: Meghan and Harry Oprah: How to watch the interview in the UK - channel and time details

CBS gave the interview a good time slot, following the popular news magazine programme 60 Minutes.

In an era when many people are making their own TV schedules, reaching that kind of live audience is unusual now unless it is a big sporting event.

Nielsen said it had the largest audience for any prime-time entertainment special so far this television season.

READ MORE: Meghan and Harry interview: The key revelations from the Oprah interview

In the interview, Meghan said she considered suicide, while Harry said he and his family were "trapped" in an oppressive institution.