Channing Tatum knows he wants to be with Zoe Kravitz "forever".

The 44-year-old actor is currently engaged to actress Zoe, 35, and hinted that after they worked together on the upcoming horror 'Blink Twice' and suggested that the best way to ascertain romantic feelings for someone is to work with them on the "hardest project" possible.

He told E! News: "Our relationship was sort of born inside of the creative process of it in a way.#

"It didn't feel any different. That was what brought us together and made us really feel like we're very connected on what we love about life, what we love about just things in general about being alive.

"It was just easy. Making movies is hard. One thing I will say is if you think you're in love with somebody and you're thinking about, ‘Do I want to stay with them forever or be with them or have a child with them or get married?’ Go find the hardest possible project that you can physically find. Go build a house, paint a room, do something!"

The 'Fly Me to the Moon' star - who has 11-year-old daughter Everly with ex-wife Jenna Dewan - recently explained that he and Zoe were "brought together" by working on the new film.

He told Extra: "Working with your partner truly is — you know, I know a lot of people are afraid of it — it was the thing that cemented us in a way.

"We started, you know, kind of grew a little bit right before we started filming, and then it's like, 'Okay, we're gonna go do this.'

"It just brought us together.”