Coin Farrell says kissing attractive co stars is great but when it comes to taking his clothes off for scenes it becomes a lot less fun.

Interviewed by ContactMusic, he said: "It's always strange to kiss someone when you know they're getting paid to kiss you back. That's the most simple, mathematical way to put it.

"But it's part of the gig and at the same time, kissing is lovely. So any time I get to kiss someone, that's great."

He stated: "When the clothes start coming off, though, that's when it can get a bit uncomfortable. And then what do you fall back on? Humor.

"That's what we do as human beings don't we? We laugh, we joke, we try to poke fun at an embarrassing situation. But there's never been a bad day at the office."