An American movie director has criticised the Irish Film Board for not funding her award-winning Irish movie project, saying she was discriminated against because she is not Irish.

Chicago-born Tamar Simon Hoffs is the director of the film adaptation of Red Roses and Petrol, which was originally written for the stage by Irish writer Joe O'Connor. The film is set in Ireland, features a mainly Irish cast and was produced by Galway production company Abu Media.

Hoffs had originally intended to film the entire project in Ireland – principally in Galway – but has said she was forced to move filming to the United States when the project was refused funding by the Irish Film Board at the last minute.

"We went to the Film Board and we were given assurances that support for the movie would go through," Hoff said. "We had everything planned and ready to go, but in the end they left us holding the bag with nowhere to go, when they decided not to give us any development money. It was so sad, because here we were, this wonderful company with this fabulous Irish story and Irish cast and we couldn't go forward as we had hoped."

Hoff said that although she was never told directly that Irish Film Board was withholding funding due to her nationality, she believed this to be the case.

Following the decision of the board, Hoffs moved the project to the US, where she "recreated the Ireland of the play in a warehouse in Valencia, California". She completed the full-length feature for less than $500,000, and the film has already been awarded several prizes at film festivals in France, Canada and the US. It goes on release in several major US cities on 27 June before opening in Ireland in July.

However, despite Hoffs' criticism of the Irish Film Board, playwright Joe O'Connor told the Sunday Tribune that he had always found the Board "warmly supportive" of his work, and he had no complaints about its decision not to fund the movie.

"I have to admit that the film version of Red Roses and Petrol is shall we say not my favourite movie of all time," he said. "I was not involved in the project myself and I found certain aspects of the film surprising when I finally saw it, especially in how it departed from the source material of my stageplay. In that context, I think the Irish Film Board is absolutely entitled to decline certain projects if they are not convinced by the entire package. They are funded by the taxpayer after all, and there have to be standards."

The Irish Film Board did not return calls to the Sunday Tribune on the allegation.