Meghan, the Duchess of Sussex, and Britain's Prince Harry, pose for a family photo with Ireland's president Michael Higgins. Picture: AP

London - The Duchess of Sussex looks "terrified" and is masking the stress of her new life as a royal with a "pained smile", says her father.

In a bombshell interview, Thomas Markle also criticised the "ridiculous" dress code Meghan has to abide by and claimed the royal family shuns him because of its "asinine" rules.

The 73-year-old admitted Meghan has not spoken to him for almost two months and pleaded with her to get in touch because he "could actually die soon" and wanted to "clear the air" and tell her how proud he is of her.

But he said the phone number he has been calling her on "is no longer picking up". Mr Markle’s latest comments are likely to cause even more disquiet at Kensington Palace following his previous indiscretions.

First, there was the furore over staged paparazzi photographs ahead of the wedding; then, in another interview, he repeated private conversations with his son-in-law Prince Harry.

In the new interview, Mr Markle said: "My thing about my daughter right now is that I think she is terrified. I see it in her eyes, I see it in her face and I see it in her smile.

"I’ve seen her smile for years. I know her smile. I don’t like the one I’m seeing now.

"This one isn’t even a stage smile – this is a pained smile. That might be just having a couple of bad days. I don’t know. It really worries me. I think she’s under too much pressure. There’s a high price to pay to be married to that family."

Mr Markle has watched former television actress Meghan, 36, adjust to her new life from his rented home in Rosarito, Mexico.

In the interview with The Sun on Sunday, he added: "My daughter’s very controlling. She likes to be in charge." He said the clothes which Meghan wears on official duty made her look "like something out of an old movie" from the 1930s, and asked: "Why do they have to cover her knees?"