Christopher Mintz-Plasse says it's a ''bummer'' Jim Carrey doesn't want to promote 'Kick-Ass 2'.

The veteran actor - who plays Colonel Stars and Stripes in the action sequel - withdrew his support of the film earlier this year, feeling it is too violent in light of the Sandy Hook school shootings, and his co-star is saddened by his decision but finds his opinion ''understandable''.

He told BANG Showbiz: ''It's a bummer because he's so good in the movie that I would love to have him promoting the movie, but with everything that's happened, it's totally understandable why [he doesn't want to].

''We really upped the ante with the violence in this one and I think with all the tragedies that have happened this year, that's on people's minds, which is terrible. Violence is always controversial - nothing you can do.''

Mintz-Plasse went on to defend Carrey's controversial decision, insisting it is difficult to envision how the film will look on screen compared to the script.

He explained: ''You read the script and you're like, 'Oh, it's violent', but when you actually see it in front of you, it's a lot more violent than you think it's gonna be on the page. He saw the finished product and he just couldn't get behind it. I respect the guy's opinion.''

'Kick-Ass 2' is in cinemas now.