"Ghost Game", which opens in Thailand on Thursday, tells the story of 10 reality television gameshow contestants who agree to stay in a haunted prison, where they must confront the atrocities that occurred there in order to win an enormous cash prize.
"We are sorry that our movie has drawn complaints from Cambodian people who are concerned about the history of the country. We had not given this enough serious thought," the movie's executive director Napat Pavaputanont said.
The film takes place in a fictional Security Prison 11, which closely resembles the Khmer Rouge's Tuol Sleng prison, or S-21, where some 16,000 men, women and children were tortured before being executed.
"We also regret if the film affects the good relationship between Thailand and Cambodia," he added.
Cambodia's culture ministry official said Wednesday it was set to ban the film, saying "Ghost Game" hurts the country's reputation by exploiting its tortured past.
Up to two million people died of starvation, execution or overwork as the communist Khmer Rouge tried to turn Cambodia into a vast collective farm in the late 1970s.
The filmmakers originally planned to shoot the movie in Cambodia, but they changed their minds due to concerns about the sensitivity of the issue. The entire movie was shot in Thailand instead.
The film's prison set is an actual prison in central Thailand, but the filmmakers hung Khmer signs that create unmistakeable references to places in Cambodia.