The happy couple confirmed on social media that they’d had a healthy son, who they have named Monte Pearce.
Guy, 48, has been in a relationship with Carice, 39, since last year after splitting with his wife of 18 years Kate Mestitz.
“A cute little package arrived and told us his name’s Monte Pearce,” Guy posted on his Twitter account.
“We think we’re gonna keep him. Placenta smoothie anyone?”
A spokesperson for Carice, who plays witch Melisandre on the hit series Game of Thrones, confirmed the baby was born in Carice’s native-Amsterdam in mid-August.
Guy had repeatedly told the media over the years that he had no desire to be a dad.
“There are enough babies in the world,” he said to The Guardian in 2007, “Besides, I don’t think I would be good for babies”.
In 2011 he told The Independent: “I believe you need to have a level of emotional consistency when you raise a child and I don’t know that I have that. It would be unfair to inflict that on a child.”
In 2012 he told the Daily Telegraph: “I’m not consistent enough to be a parent – I blow too hot and cold.
“I completely acknowledge that having kids has got to be one of the most incredible things in the world, but it’s also really hard work.”
But Guy seems to have mellowed since meeting Clarice and becoming parents together.
He posted a touching tribute to his late dad on Twitter to commemorate the 40th anniversary of the tragic plane crash that took his life.
“Aug 6 1976 – Dad never made it home from that test flight. A profound effect, only amplified as I await my own child.”
The Aussie star also shared a series of shots of him holding cute animals, clearly showing he always had a paternal side.
Alongside a collection of images showing him holding a puppy and a tiger cub, amongst other animals the actor wrote: “The baby will be like one of these right?”
This post was last modified on 30/08/2016 11:02 am