Meghan Markle has backflipped on her denials she helped the authors of a flattering biography about her marriage to Prince Harry, and their exit from the British royal family.

Meghan and Harry have long denied helping the authors of Finding Freedom, which was released in August.

However, her lawyers conceded on Wednesday (British time) that the Duchess of Sussex did allow some information to be passed via a third party to the book’s authors.

They said this was because Meghan was concerned about “her father’s narrative” and wanted “the true position” communicated.

The duchess is suing the owner of Britain’s Mail on Sunday, Associated Newspapers, over articles that included parts of the handwritten letter she sent to her estranged father Thomas Markle in August 2018.

She alleges publication of the letter was a misuse of private information and breached her copyright. Her lawyers are seeking aggravated damages.

Meghan and her father have not spoken since he pulled out days before her wedding to the prince in May 2018 because of ill health. He subsequently gave several media interviews.

In September, the court ruled the Mail could amend its case to include details from the recently published Finding Freedom.

The paper’s lawyers argued the book showed Meghan intended some private details to become public, including the letter, as part of a campaign to portray her in a positive light.

But Meghan’s legal team repeated their position that neither she nor Harry had co-operated or been interviewed for the book.

Thomas Markle and daughter Meghan in an undated photo.

In a stunning admission, Meghan’s court documents were amended and released on Wednesday. They now show she spoke with someone who was approached by Finding Freedom authors Omid Scobie and Carolyn Durand.

“Accordingly, she indicated to a person whom she knew had already been approached by the authors that the true position as above … could be communicated to the authors to prevent any further misrepresentation,” the documents state

But, it says, neither the duke nor the duchess co-operated with Scobie or Durand to reveal their “version of events”.

The documents also reveal that Meghan sought advice from two senior members of the royal family before writing the contentious letter to her father.

Her legal team rejected the Mail‘s claim the letter was part of a media strategy, stating instead that it followed “advice from two senior members of the royal family” on how to get her father to stop talking to the press, her lawyers said.

Meghan created a draft over several weeks, sharing it with Harry and communications secretary Jason Knauf, who gave feedback but no actual wording, the document said.

“The claimant and the claimant alone created the electronic draft, which she then transcribed by hand to her father as the letter,” her lawyers said, adding Meghan followed palace protocol.

The case has raised the possibility of Mr Markle giving evidence against his daughter in court.

However, in a ruling earlier on Wednesday, judge Mark Warby said Mr Markle did not appear to be an important witness in the case and it was inaccurate to view it as a family battle.

Last month, Judge Warby granted a request from the duchess’ legal team to delay the trial for nine months until late 2021, citing a “confidential” reason.

-with AAP