Meghan Markle’s father has threatened to air the Duchess of Sussex’s “dirty laundry” in a new interview days after giving birth to her daughter Lilibet.

Thomas Markle has begged to be forgiven by Prince Harry and Meghan so that he can meet his granddaughter in a trailer for an explosive interview with 60 minutes Australia.

He has not spoken to his daughter for three years after Meghan cut off contact with her estranged father after he was caught staging paparazzi shots ahead of the royal wedding, according to reports.

The interview, set to air on Sunday shows Mr Markle explains how he is desperate for a truce and wants forgiveness for “one dumb mistake”.

In a 40-second trailer for the interview, he said: "I haven't spoken to her (Meghan) since two days before they got married.”

He also claims to have only heard about the birth of his granddaughter “on the radio”.

"I'll be very disappointed that I don't get to hold my granddaughter,” he said.

Despite his pleas for forgiveness, the 76-year-old risks damaging his relationship with the Duke and Duchess of Sussex even further after threatening to air “dirty laundry”.

He said: “You want dirty laundry? This is the first time I’ve ever discussed these things.”

Bournemouth Echo: Meghan Markle has not spoken to her father since two days before the royal wedding in 2018. (PA)Meghan Markle has not spoken to her father since two days before the royal wedding in 2018. (PA)

The new interview comes as Prince Harry and Meghan Markle issued a legal warning to the BBC over claims the Queen was “never asked” by the couple if they could name their daughter Lilibet.

he Duke and Duchess of Sussex are settling into life as a family of four after the birth of their daughter Lilibet “Lili” Diana.

Meghan and Harry said it was a “very special time” and described the baby girl as “more than we could have ever imagined”.

Lili, a younger sister for the Sussexes’ two-year-old son Archie Mountbatten-Windsor, was born at 11.40am on Friday June 4 at Santa Barbara Cottage Hospital in California weighing in at 7lb 11oz.

Lilibet is the Queen’s family nickname and the choice pays tribute to the monarch at a challenging time for the Windsors, who are mourning the loss of the Duke of Edinburgh.

In a message of thanks on their Archewell website, Harry and Meghan said: “On June 4, we were blessed with the arrival of our daughter, Lili.

“She is more than we could have ever imagined, and we remain grateful for the love and prayers we’ve felt from across the globe.

“Thank you for your continued kindness and support during this very special time for our family.”