The comment was made in 2011 when the actor appeared at Comic Con to talk about the series.
While discussing his character Khal Drogo, he says: “But as far as sci-fi and fantasy, I love that there’s so many things you can do, like rip someone’s tongue out of their throat and get away with it and rape beautiful women.”
After a video of him making the comment was shared across social media amid the sexual assault allegations made against Harvey Weinstein, the actor took to Instagram to apologise.
The 38-year-old wrote: “I awoke in Australia to the justified reactions by many people to a distasteful joke I made years ago in Hall H for which I am sorry.
“I am still severely disappointed in myself at the insensitivity of my remarks that day. I know my sincerest apology now won’t take away those hurtful words.
“Rape and sexual harassment can reach anyone and I have seen first hand it’s painful torment among members of my own family and friends.
“I made a truly tasteless comment. It is unacceptable and I sincerely apologise with a heavy heart for the words I said. All apologies, Jason.”
The American actor’s apology comes after his ‘Justice League’ co-star, Ben Affleck, also apologised after footage of him groping MTV host Hilarie Burton during a 2003 interview resurfaced.
Just days earlier, the ‘Gone Girl’ actor posted a statement on Facebook in response to sexual harassment accusations about film producer Harvey Weinstein, with whom he has collaborated on several occasions.
The movie boss is now being investigated by police on both sides of the Atlantic, as allegations against him mount.