“Harry, Meghan and Archie will always be much-loved family members.”

Buckingham Palace has come under mounting pressure to respond to the claims made in an Oprah Winfrey interview first broadcast on Sunday in the US, followed by a broadcast in Britain on Monday. More than 49.1 million people around the world tuned in, according to US television network CBS on Tuesday.

The interview triggered a crisis unseen since the anguished days of Harry’s late mother, Diana, in the 1990s, and set off a whirl of speculation about the identity of the senior royal who asked how dark Meghan and Harry’s child’s skin would be before he was born.

Meghan, whose mother is black and father is white, also spoke about how she had suicidal thoughts, but failed to receive any support during her time in the royal family.

Winfrey was left open-mouthed by the racism claim, which reportedly left the palace in turmoil and scrambling how best to address it.

Meghan’s father says she went ‘way over the top’ by accusing royal family of racism

Prince Charles, Harry’s father and the heir to the throne, earlier ignored a question about what he made of the interview, as he made his first public appearance since the row erupted.

A YouGov poll of 4,656 people after the interview aired on British television on Monday indicated almost a third (32 per cent) felt the couple was unfairly treated, the same proportion as those who thought the opposite.

But older people were more likely to side with the royal family, the poll suggested.

Harry and Meghan’s claims have been likened to a bomb being dropped on Britain’s most famous family and one of the country’s most revered institutions.

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Prince Harry and Meghan stepping back hits Chinese social media

Prince Harry and Meghan stepping back hits Chinese social media

Attempts have been made to draw in Prime Minister Boris Johnson, who has himself been accused of racism during his time as a newspaper columnist.

But he refused to comment, even as political calls mounted for a full inquiry and the White House and former US secretary of state Hillary Clinton spoke out.

However Zac Goldsmith, a junior British foreign minister and close ally of Johnson, said former army captain Harry was “blowing up his family”.

Johnson’s spokesman declined to say whether Goldsmith was speaking for the government.

Meghan and Prince Harry lift lid on royal rift in Oprah interview

The level of controversy about the royals has not been seen since the 1990s, during the very public collapse of the marriage of Harry’s parents.

His mother, Princess Diana, collaborated with the author Andrew Morton in a revealing 1992 biography and gave a bombshell BBC television interview in 1995.

In it, she said both she and Prince Charles had been unfaithful, how he was unfit to be king, and that she felt isolated, struggling with self-harm and bulimia.

Morton said Harry and Meghan’s claims would “shudder down through the generations in the same way that Diana’s did”.

But Meghan’s estranged father Thomas Markle defended the royals, saying he hoped the skin tone comment was “just a dumb question”.

“It could just be that simple, it could be somebody asked a stupid question, rather than being a total racist,” he told Britain’s ITV.

The couple dramatically quit royal life last year and now live in California with their young son, Archie, and are expecting their second child, a daughter, this summer.

Additional reporting by Reuters