Cate Blanchett says having children is "addictive".

The 'I'm Not There' actress recently gave birth to third son Ignatius Martin with her husband Andrew Upton and says the couple can't wait to further expand their brood.

Cate - who also has sons Dashiell John, six, and four-year-old Roman Robert with Andrew - said: "Having kids is very addictive, if you can, if you're able to and it's your choice and you've got a supportive relationship."

The actress recently revealed becoming a mother has made her a better person and improved her life considerably.

She said: "You realise how much love you're actually capable of. It's like more doors open in your personality that you didn't even realise were there.

"It's a trip, being a parent, a privilege - even though it means you get a lot less sleep!"