The Romanian director Cristian Mungiu says: “I am not jumping for joy every day. Instead, I’m overwhelmed. Everybody wants something from me. All these changes, these obligations. All I can do right now is just smile, talk to people and be polite.”

The 39-year-old film-maker is describing the hell of great success. With only his second feature, the harrowing 4 Months, 3 Weeks and 2 Days, Mungiu has created a touchstone movie phenomenon that is both personal and political, emotional and intellectual, locally observed and internationally acclaimed.

The film, about the efforts of two students to procure an illegal abortion in Nicolae Ceausescu’s Bucharest, won the Palme d’Or at the 2007 Cannes Film Festival and has been nominated for a Golden Globe.

“It’s complicated,” he adds, ruminating on the double-edged nature of instant fame. “Everything’s changed, and there’s very little time left for me.”

Which is ironic, given that the film was never meant to be Mungiu’s big statement. It was envisaged as a wry look at Soviet-era Romania, with jokes and satirical asides. However, when a young actor friend read the script, then titled Tales from the Golden Age, it was clear that a change of approach was required. “He said to me: ‘This is so hilarious. It must have been so funny to live through this period of Romanian history.’

“It wasn’t exactly what I wanted to hear, and I tried to explain that the period wasn’t funny at all.”

Mungiu decided that gags were out and realism was in. He focused on the real-life account, told to him by an old acquaintance, of an illegal abortion during one long day in 1987 (abortions were outlawed in 1966).

Here two girls, the willowy and pregnant Gabriela (Laura Vasiliu) and the tough, pragmatic Otilia (Anamaria Marinca), drift from the bustle of a student residence to a bleak hotel where they meet a sinister abortionist and sexual opportunist called, ironically, Mr Bebe – pronounced “bay-bay” (Vlad Ivanov) .

As the abortion proceeds, Otilia tries to maintain control over the situation, despite being abused by Bebe, facing the possible death of her friend (Gabriela is more than four months pregnant, hence the movie’s title) and dealing with the demands of her middle-class boyfriend Adi (Alexandru Protocean). In one standout scene Otilia has to sit through a frivolous birthday party for Adi’s mother while Gabriela is in the hotel room across town with a potentially fatal saline solution pumping around her innards.

“But I never wanted it to be a film about abortion,” explains Mungiu. “For me it’s a film about much more than that. It’s the story of one day in the life of this girl, Otilia, and the encounters she has and how they affect her. I’m relating her story without any kind of judgment, and I invite the audience to have their own opinions about the film.”

Mungiu’s film manages to deal with abortion without advocating any stance other than compassion. It illustrates what happens when a woman’s right to choose her biological destiny is removed, and yet it also shows a picture of abortion that would please the most adamant pro-lifer. The viewpoints cancel each other out, leaving a moving portrait of two lonely women who bond in an unforgiving regime.

“It’s very difficult to explain why the film moves so many people,” says Mungiu, who shot the movie in 2006 for €600,000 (£420,000). “But I honestly believe that it has a soul. As soon as we finished editing it we knew that we had something strong, emotional and balanced. It is a film that speaks about something important without ever being preachy.”

The film stormed Cannes and made Mungiu a hero at home – the Romanian President, Traian Basescu, awarded him a medal, the Romanian Star, for his services to the nation’s film industry. But the audience’s motivations for seeing the film, Mungiu says, are diverse. “The older generation finds that the film is a healing process. The younger generation is impressed by it, but doesn’t necessarily relate to it as part of today’s Romania. The others just come to see the film that won the Palme d’Or.”

Which is all good news for the doctor’s son and former literature teacher who was inspired to make movies by the inanity of 1980s Soviet cinema. “I used to watch these social realist communist films where the biggest dramatic conflicts involved, say, a factory worker who was the best on the production line but also the best ball player and didn’t know which one to do. I’d come out and go: ‘I have no idea what they’re talking about! These people look like us, talk like us, but they’re aliens! I could do better than this.’ ”

He had to wait for the fall of communism, however, before he could join the film programme at the University of Bucharest (places were normally reserved for sons and daughters of party members or famous actors). He graduated in 1998, and directed three short films and a feature called Occident – a bittersweet ensemble about poverty in Romania, and a hint of what 4 Months might have been without the intercession of his actor friend.

Right now, Mungiu says, his greatest challenge is to start writing a new movie in between all the 4 Months promotion – the film is Romania’s Academy Award entry for Best Foreign Language Film. Even so, he doesn’t begrudge his film’s success for a moment.

“People come up to me and go: ‘You know, I never thought about it this way before.’ And that’s the reaction that keeps me going. Not the awards. Not anything. Honestly.”

4 Months, 3 Weeks and 2 Days is released on Jan 11, 2008

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