King Charles 'illegitimate child' says he is 'not afraid' of truth

King Charles illegitimate son is determined to tell the world his truth.

The 53-year-old Simon Charles Dorante-Day, says he will not give up until the new monarch admits welcoming him with then-lover Camilla.

Speaking to 7NEWS, Simon added that he is not 'afraid' to ask for his right, now that his dad is the King.

"Not really," he said. "Like I said, the mountain doesn't change, it's still a mountain.

"I'm going to climb it, so - I've got to climb it to get over it, that's the way it is."

Simon's wife supported him: "And we appreciate the opportunity to let him know that we haven't given up.

She added, "and he'll still see us.

"We have not given up and we will address him via law L.A.W and lore L.O.R.E."

Earlier, Simon revealed: "It's frustrating. To me, there's a mountain in front of me, whether it's male or female, whether it's the Queen or whether it's Charles, I've still got that mountain to climb to get to the truth.

"And that's what it's about, is the truth," he said.