Jessica Biel isn't ready to have children because she has enough trouble looking after her dog Tina.

"Not for me at this moment. I have a dog and that is hard enough!"

Speaking at the Hollywood premiere of new animated film 'Planet 51', she said: "I haven't done a lot of M4 machine gun shooting in my life and I'm doing that now a lot, it's amazing to understand how to run those weapons. I know it's a little hardcore but it's what I've been doing. It's challenging."