Meghan Markle has accused the British royal family of peddling lies against herself and her husband Prince Harry, in an escalating transatlantic war of words before a tell-all interview with US chat show host Oprah Winfrey.

The explosive claim is the latest salvo in an increasingly heated public relations battle between the British institution and the US-based couple.

Meghan Markle
Meghan Markle and her husband Prince Harry have taken legal action against several media publications, alleging invasion of privacy Photo: POOL / Tolga AKMEN

Harry and Meghan, who married in a fairytale wedding in 2018, stepped down from frontline royal duties last year, in part blaming media intrusion for their decision to move to North America.

But a steady drip of stories in Britain about the Duke and Duchess of Sussex, as they are formally known -- and tit-for-tat responses -- is becoming a torrent as the broadcast approaches this weekend.

The new clip released by US broadcaster CBS came just hours after Buckingham Palace said it was probing claims that Meghan had bullied royal household staff during her time in Britain.

Prince Harry and Meghan Markle
Meghan Markle says the British royal family is 'perpetuating falsehoods' about her and her husband, prince Harry Photo: AFP / Daniel LEAL-OLIVAS

"I don't know how they could expect that after all of this time we would still just be silent if there's an active role that 'The Firm' (royal family) is playing in perpetuating falsehoods about us," she told Winfrey.

UK tabloids
The split from the royal family has become increasingly acrimonious, but has been fodder for Britain's newspapers Photo: AFP / DANIEL LEAL-OLIVAS

Buckingham Palace said it would not respond to Meghan's latest comments, and instead focused on publicising the 94-year-old Queen Elizabeth II's daily engagements.

But there was a predictable frenzy in the British media.

Veteran royal commentator Richard Kay likened the row to the "War of the Waleses" in the 1990s when the marriage of Harry's parents crumbled.

The British Royal Family
The family is sometimes referred to as 'The Firm' Photo: AFP / Daniel LEAL-OLIVAS

Heir-to-the-throne Charles, the Prince of Wales, and Diana, princess of Wales, gave unprecedented television interviews that lifted the lid on their troubled relationship -- and extra-marital affairs.

Their "bitter and acrimonious battle for public sympathy" was similar to that of Harry and Meghan, he wrote in the Daily Mail.

Prince Harry and Meghan Markle
The fairytale wedding in May 2018 was one of the events of the decade Photo: POOL / Ben STANSALL

Royal expert Victoria Murphy told AFP the interview put the popularity of the monarchy on the line.

But she said the row had gone beyond criticism of the institution -- and could burn any personal bridges Harry and Meghan still have.

"There's only so much you can separate the individuals and the people from their roles and the positions that they have within "The Firm", and if you're attacking one, then you're also attacking the other," she added.

British Royal Family Tree
The British royal family tree Photo: AFP / Sophie RAMIS

But Omid Scobie, royal editor of Harper's Bazaar US, and co-author of a sympathetic biography of Harry and Meghan, "Finding Freedom", said it was merely a chance for them to tell their side of the story.

Meghan, a mixed-race former television actress, was likely to address her claims that she faced racism in the British press and on social media, as well as their "troubles" in the monarchy itself, he added.

But he said the "noise" before the event would die down.

"In the end it ends up being OK and I think that that'll be exactly the same with this Oprah special," he added.

There have been calls for the couple's interview, due to be broadcast in the United States on Sunday, and in Britain early Monday, to be rescheduled.

Harry's grandfather, the queen's husband Prince Philip, 99, has been in hospital for more than two weeks, and on Wednesday underwent a procedure on a pre-existing heart condition.

Others called it "inappropriate" but British media quoted a source close to Harry and Meghan as saying the broadcast would still go ahead and they had no say in the matter.

"The programming and all the rest of it is ultimately up to CBS," they added.

Harry and Meghan's acrimonious split from the royal family was made permanent last month, when the queen removed their honorary titles and patronages.

That followed nearly 12 months in which both sides have tried to control the narrative of their departure, which has polarised opinion on both sides of the Atlantic.

Harry, 36, said in a clip of the Winfrey interview released earlier this week that he feared "history repeating itself" had they stayed, in a reference to the press hounding of his mother.

Diana died in a high-speed car crash while being chased by paparazzi photographers in Paris in August 1997.

The bullying allegations, first reported in The Times newspaper on Wednesday, however, step up the war of words, with some commentators likening it to the constitutional crisis of 1936.

Then, king Edward VIII abdicated to marry Wallis Simpson, who like Meghan was an American divorcee.

Meghan, who is 39 and pregnant with the couple's second child, said the latest claims against her were a character assassination, and an attempt to "peddle a wholly false narrative" before the Winfrey interview is broadcast.

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