Northern Irish actor Jamie Dornan apologised to his Fifty Shades Of Grey co-star Dakota Johnson before they filmed "heinous" S&M sex scenes together.

The model-turned-actor, who plays bondage-loving businessman Christian Grey in the forthcoming adaptation of E.L. James' saucy book, performed a number of highly-intimate scenes with Johnson, and he would say sorry to his co-star before filming the more brutal sequences.

He tells Britain's Notebook magazine, "I got through (sex scenes) in Fifty with a lot of apologies. You have to keep the intensity there, but maintain professionalism. At the end of the day, we're all human beings and it can be uncomfortable to film things like that. So I just tried to make light of it.

"If I was about to be doing something particularly heinous to Dakota, I would apologise in advance and say, 'I'm probably not going to derive a huge amount of pleasure out of this. I want you to know that'."

Fifty Shades of Grey is due for release this week (beg09Feb15).