Ryan Reynolds has joked Lionel Richie is responsible for Blake Lively's pregnancy.

He quipped of the conception: "Yeah, ya know, [I] just played a little Lionel Richie, and the mood hit!"

And the 'Deadpool' star - who has 20-month-old daughter James with his spouse - admitted the "extraordinarily pregnant" actress blames him for her not being able to get out and about as much as she'd like to.

He told People magazine: "I'm a big outdoorsman. My relationship with the outdoors is a long, storied one and something I value greatly.

"I love doing it with my family. I take my daughter with me all the time on hikes. My wife is just extraordinarily pregnant, so there's not a lot of hiking going on, which I'm told is my fault!"

But while the former 'Gossip Girl' star's changing figure might keep her largely indoors, Ryan still has a hiking partner.

He said: "I take my daughter out all the time. I live upstate New York, as well, so I'm able to get out there, and it's all just the backyard and the forests."

Ryan is supporting Eddie Bauer and American Forests' The One Tree initiative and #Hug2Give campaign - which aims to raise money for conservation efforts - because he is keen for his own children to have the outdoors opportunities he had when he was young.

He explained: "I like to think that this movement is galvanised enough that we can actually turn back the clock on some of the damage we've done and really create a space in the world that our kids can enjoy and experience what we experienced when we were young, their age.

"I think about it all the time: Is my daughter going to have the same opportunities I had as a kid? And I hope that's gonna be true. So I'm doing my part, big and small, to see that that happens."