Naomi Watts says having a ''good relationship'' with her ex-partner Liev Schreiber is an ''absolute priority'' for the sake of their family.

The 51-year-old actress who raises Sasha, 12, and Samuel Kai, 10, with her former partner, admits that while their public break up in 2016 was difficult, they have both stayed dedicated to keeping a healthy relationship in order to co-parent to the best of their abilities.

Speaking to The Sunday Times' Style magazine, the King Kong star said: ''Having a good relationship has always been our endgame, and we've put a lot of energy and effort into making that so.

"It's not always a cakewalk, as they say in America. But it makes complete sense that it is an absolute priority, because it really matters to the children.

"You can see how there are so many things that can make a kid feel anxious, and knowing that their parents can be in the same room and joyfully, it means a lot to them.''

Last year Schreiber opened up about adjusting to life after their 11-year-relationship ended.

"It's always hard, you know? You build a life with someone and things change," he said. "And I think the way that we’ve looked at it is that we’ll always be partners with these kids," he told Sunday Today.

Schreiber also said keeping a friendship with Watts was a priority for the sake of their children.

"It’s important to support each other," he said. "I was making some jokes at breakfast about Mommy with the boys and their eyes light up when I talk about her. You can see how important it is to them that their parents care about each other."

Watts also opened up about the split, admitting that there are "good days and bad days."

"I mean, I'm single, I’m co-parenting. I’m doing okay," she told Vogue Australia.