Mike Medavoy, producer of The Promise, said those complaining about the film should "move on" and accept historical fact.

"I couldn't understand why this film hadn't been made before," he told The Telegraph. "Now I know."

Mr Medavoy, who as vice president of production for Universal was responsible for films such as Rocky, Terminator and One Flew Over the Cuckoo's Nest, said he did not anticipate so strong a backlash against this film.

Charlie Chaplin was once in talks to tell the story, he later found out, but the film was dropped under Turkish pressure.

"And nowadays it's perhaps even more relevant - with what's going on in Syria. There are people who still deny the Holocaust, too."

The 67-year-old producer, whose films with his own company include Black Swan, Shutter Island and The Thin Red Line, said he was not aware of the sensitivities before he embarked on the film, but "knew there would be some issues" when the film team came to him with the idea.

He was not warned off the film, though.

"If they did, they'd have gotten to the wrong guy," he said.

The campaign seems to have worked but also triggered an equal and opposite backlash from Armenians and other supporters of the film. Out of the 126,000 ratings on the site 63,000 of them are ten stars and 61,000 are one star. There are barely any rankings inbetween.