Jason Clarke has dismissed criticism that 'First Man' is anti-American.
Ryan Gosling portrays late astronaut Neil Armstrong in the drama, which retells NASA's mission to land a man on the moon for the first time, and the movie received criticism after he said Armstrong's moonwalk "was widely regarded not as an American, but as a human achievement".
However, co-star Jason, 49, has hit back at critics and insisted that the movie is patriotic but also celebrates "humanity and mankind".
Speaking to The Hollywood Reporter at the Deauville Film Festival, he said: "It's nonsense, it's just nonsense. The film itself can be interpreted as patriotic. It's just silly and naive I think. Of course it celebrates one of the greatest acts of America and Americans and humanity and mankind.
"People look for conspiracy theories rather than looking for the truth."
Jason's comments come after director Damien Chazelle insisted that the decision not to include a flag-planting scene on the moon was not an anti-American message.
Chazelle said: "In 'First Man' I show the American flag standing on the lunar surface, but the flag being physically planted into the surface is one of several moments of the Apollo 11 lunar EVA that I chose not to focus upon.
"To address the question of whether this was a political statement, the answer is no. My goal with this movie was to share with audiences the unseen, unknown aspects of America's mission to the moon -- particularly Neil Armstrong's personal saga and what he may have been thinking and feeling during those famous few hours. I wanted the primary focus in that scene to be on Neil's solitary moments on the moon - his point of view as he first exited the LEM, his time spent at Little West Crater, the memories that may have crossed his mind during his lunar EVA. This was a feat beyond imagination; it was truly a giant leap for mankind. This film is about one of the most extraordinary accomplishments not only in American history, but in human history. My hope is that by digging under the surface, we can better understand just how difficult, audacious and heroic this moment really was."
Neil Armstrong's sons have also defended the movie and urged viewers to watch it before judging.