United Kingdom, Sept. 6 -- Nicole Kidman has insisted she doesn't want to be her daughters' "best friend".

The 59-year-old actress - who shares two daughters, Sunday, 18, and Faith, 15, with ex-husband Keith Urban - explained that when it comes to her parenting approach, she doesn't want to prioritise being pals with her kids.

Instead, Nicole, who also shares two adopted children, Bella and Connor, with ex-husband Tom Cruise, would rather her offspring see her as their "rock".

She told Australia's Daily Telegraph newspaper: "You're a mother first. You're a mother, but you're also a guide, a mentor, a safe haven, the place you can always come home to.

"But ultimately, as I always say to my kids, no, I'm not here to be your best friend,...