Cate Blanchett says "spooning" in bed is the secret to a happy marriage.

The Oscar-winning actress, who has three sons with husband Andrew Upton, told Oprah Winfrey: "Someone once said to me, and I think it's quite true, that if your bodies actually fit together when you're sleeping in bed — I'm not going to get into too much detail — you're in good stead.

"When you can spoon with someone, then you're OK. Because you might not vote the same way, you might not have the same politics, but sometimes that works for people."

Blanchett and playwright husband Andrew Upton have three sons: Dashiell, 6, Roman, 3, and Ignatius, who was born in April.

The Academy Award-winning actress appeared with Harrison Ford in the movie "Indiana Jones and the Kingdom of the Crystal Skull," which was a summer hit.

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The Associated Press contributed to this report.