Saoirse Ronan has expressed her admiration for activists, but said she could never be called one.
The 26-year-old Little Women star told a master class at the Toronto International Film Festival that others did far more to change the world.
However, Ronan, an ISPCC ambassador who has also backed the #MeToo movement, said she welcomes the chance to use her star power to do some good.
"I don't consider myself an activist. It would be unfair to say that, given the very small amount of work I've done with people who really dedicate their lives to it," she said.
The actress, whose new film Ammonite received rave reviews at its premiere in Toronto, said her role in activism was backing those "doing the real legwork".
During a discussion of her life and career, she told of how she grew up in front of the camera from starring in Atonement at the age of 13 to Brooklyn when she was 20.
"I was absolutely a wreck, the difference between the way I was as myself and as an actor on Brooklyn versus the way I was on Atonement," she said. "I was 20, so the hormones were hanging all over the place.
"I went back not even to Dublin, but where I grew up and I hadn't been there in years, and that represented an important yet an older path in my life that I will always remain connected to, but I was moving past that."
The need to get Brooklyn right had Ronan filled with terror.
"I had never been aware of the camera in a negative way or had it paralyse me," she said. "But I was feeling that a bit on Brooklyn, in terms of, 'What am I doing with my face?'
"That film gets to me in a way that nothing else I've done has."
Ronan was seen at the weekend cuddling up to her actor boyfriend Jack Lowden in London's Notting Hill.