After Prince Harry and Meghan Markle welcomed their newborn daughter Lilibet Diana Mountbatten-Windsor, Piers Morgan insulted them.

The former Good Morning Britain anchor, who has been an outspoken critic of the pair, rushed to Twitter after they announced on Sunday that they had welcomed a baby girl earlier this week.

The baby girl's name is Lilibet, or Lili for short, after the Queen's family nickname, but she will be called Lili, and Diana after Harry's later mother.

Piers also joked that he wouldn't tweet about the baby announcement because he wanted to protect the couple's privacy.

"To those requesting my reaction to the new royal baby, I am honoring her parents' continual appeals for privacy and refraining to comment," Piers wrote on Twitter.

He was referring to the couple's claims that they had stood down as senior royals in order to live more private lives, only to later do endless interviews.

Harry and Meghan's baby is a new cousin for Prince George, Princess Charlotte, and Prince Louis, as well as a little sister for their son Archie, who was born in 2019.

The couple's press secretary said in a statement: "The Duke and Duchess of Sussex, Prince Harry, and Meghan Markle, are overjoyed to welcome their daughter, Lilibet "Lili" Diana Mountbatten-Windsor, into the world.

"Lili was born on Friday, June 4th at 11:40 a.m. at Santa Barbara Cottage Hospital in Santa Barbara, California, under the expert care of the doctors and nurses.

"She weighed 7 pounds 11 ounces. Both mother and infant are in good health and are adjusting to their new surroundings.

"Her Majesty The Queen's family nickname is Lilibet, and Lili is named after her great-grandmother.

"Diana was chosen as her middle name in honor of her late grandmother, The Princess of Wales.

"This is the couple's second child; Archie Harrison Mountbatten-Windsor, their two-year-old son, is the couple's first.

"As they enjoy this unique time as a family, the Duke and Duchess thank you for your warm thoughts and prayers."

It comes after Piers again slammed Meghan in an appearance with 60 Minutes Australia, calling her a "liar."

On the show, he said: "Meghan Markle had complained to my supervisor at ITV on Monday night, which I was unaware of at the time.

"It was requested that I apologize for not believing her, or else I would be asked to leave my seat.

"I thought there was hypocrisy in the interview, and I thought there were outright lies.

"I considered my duty as holding them accountable in the same way I would a government minister, and I had to quit the job within 36 hours for doing so."

He said, " "You can't have strong opinions about things, and you can't believe a liar like Meghan Markle.

"I'm sorry if I have to call her that, but she is a liar. That has been demonstrated and proven."

After 50,000 people, including Meghan, complained about Pies' statements against the Duchess of Sussex, he left Good Morning Britain.

He had previously criticized the couple's interview with Oprah Winfrey, saying that he didn't believe anything Meghan said.

This included Meghan's brave disclosure that she had suicidal thoughts and her assertion that the Royal Family had turned her down for treatment.