London, Nov 17 - Actress Nicole Kidman says she will never write a memoir as she doesn't want to unravel secrets about her private life.

Imdb. com quotes the actress as saying that she will always stay tight-lipped about her almost 10-year marriage to ex-husband Tom Cruise, their adopted children and his beliefs.

"I would never write a memoir. There are things that happen behind closed doors and that's where they belong. I'm not secretive. I'm protective," said Kidman.