Mr Markle said the book would be “about the good years with my daughter and my fond memories of her growing up”.
Opening up to The Sun, Thomas revealed his heartbreak at being shut out by Meghan since she joined the royal family.
“This whole thing should have been one of the proudest moments of my life,” he said.
“Now it’s like a dream that has turned into a nightmare. The royals and Meghan can help end this nightmare by simply giving me a call. To this day, I cannot think of anything I’ve done to deserve how I’m being treated now.
“I’ve been a good father I’ve done nothing wrong. Axe murderers kill 19 people and their daughters still come and visit them in prison.
“It’s just incomprehensible for Meghan to treat me this way.”