Thompson said the film's subject matter was "tricky"

Thompson stars in Imagining Argentina, which combines magic realism and graphic torture scenes.

Critics greeted it with boos and cries of "disgrace" during a preview screening on Monday.

But Thompson said the film's subject matter and style meant it was bound to be criticised.

She said: "When you're dealing with a subject that is as tricky and controversial as state-sponsored terrorism and you combine it with magic realism you're treading a very thin line and some people are going to have that response."

The film, directed by British director Christopher Hampton, is set during Argentina's political upheaval of the mid-1970s.

It attempts to relate the story of 30,000 people who were imprisoned or murdered under the former political regime.

Thompson plays a journalist who goes missing after writing an article about the country's so-called "disappeared".

Responding to the critics, Thompson said: "We don't care because we were there and we were working with people who went through these atrocities."

Hampton said he had tried to portray the mental opposition of the people to state repression, against which they would be powerless.

He added: "You can't take on a subject like this without being extremely contentious. Whatever people think of the film, this is a subject that needs discussing, it needs to be aired, to be talked about."