Chris Pratt says Katherine Schwarzenegger's pregnancy cravings have been ''tough''.

The 30-year-old author is expecting her first child with her husband and he has revealed her current addiction to pickles and ice cream is ''tough'' on both of them.

Speaking to Extra, he said: ''It's been tough. Pickles and ice cream ... I never thought I would like 'em ... Can I be honest with you? I found myself complaining the other day about a little bit of low back and hip pain and how in quarantine I've gained a little weight ... and she just looked at me sweetly. I was like ... 'Oh, right, right, I don't really get to complain about that to you right now, do I?'''

Meanwhile, Katherine and Chris Pratt are said to be ''so happy'' to be expecting their first child together.

A source said: ''Chris and Katherine are so happy. They wanted to enjoy this time privately for as long as possible, but now that Katherine is showing more, they're excited to share the news with everyone.''

The news came after Chris admitted his wife will make ''a great mum one day''.

The 40-year-old actor said: ''She has changed my life for the better in so many ways. My heart, my soul, my son I feel are all so safe with her. She's a great step mum. She's, God willing, going to be a great mum one day. She's got great parents, great siblings, she fills in all my many deficits. My nickname on these press tours is Yard Sale because I'm such a scatterbrain. And she doesn't mind helping me with that stuff. It's a good match.''

Katherine's father Arnold Schwarzenegger has also spoke about the prospect of his daughter starting a family with Chris - whom she married in June 2019 - as he said he is ''looking forward'' to becoming a grandfather, but isn't ''pushing'' the pair to have kids.

He explained: ''I don't push it because I know it's going to happen eventually. It's up to Chris and her when they want to do that but I'm looking forward it to, yes.''