A sudden revival of Italian cinema after half a century in the doldrums has engendered a heated political debate, with Italy's resurgent Right attacking a new wave of films for showing the world only the country's “dark heart”.

The success at the recent Cannes Film Festival of Il Divo, directed by Paolo Sorrentino, and Gomorra, directed by Matteo Garrone, both under 40, has been greeted by critics as proof of a return to the glory days of Italian cinema in the 1940s and 1950s. Both films, which deal in different ways with endemic corruption and the Mafia, are showing to packed houses.

Il Divo, which looks at Italy's often troubled post-war history through the career of Giulio Andreotti, who was Prime Minister seven times, won the Cannes Grand Prix; Gomorra, a gritty, violent depiction of life in Naples under the Camorra, the local Mafia, won the Jury prize. “They are twin films, two children carried in the same womb, with a common theme of what is lurking behind the facade of a Western democracy,” Sergio Castellitto, an actor who was on the Cannes jury, said.

The screenwriter Giancarlo De Cataldo praised the new wave of theatre and film directors for not being afraid to depict Italy as an “immobile and reactionary” country riddled with crime and corruption and saddled with “dark mysteries” from the past. Marrone and Sorrentino were emulating the great Italian directors of the past such as Roberto Rossellini, Federico Fellini and Luchino Visconti.

The films have arrived at a time of deep divisions in Italian politics. The new right-wing Government, led by Silvio Berlusconi - serving his third term at the age of 71 - is seeking to blame Italy's ills on illegal immigrants, Roma Gypsies and the Mafia. But the reality as depicted by the new films is that not only the ruling class but many ordinary Italians are complicit in a corrupt system. “You sometimes have to do evil in order to do good,” Mr Andreotti is made to say in Il Divo. “God knows this, and so do I.”

For Luca Barbareschi, one of Italy's leading actors and now a centre-right deputy, this was outrageous. Gomorra and Il Divo were good films, he acknowledged, “but for every film of this kind we should export another ten which show our country in a positive light. Instead we are only good at showing the world our black side. It's a kind of self-laceration”.

Mr Andreotti himself, now 89, was also incensed by Il Divo, in which he is played by the actor Toni Servillo - who is also a Mafia boss in Gomorra. “This is too much,” he was heard to protest during a private screening in Rome - at the point where the film shows him “confessing” to involvement in a series of scandals.

They include the murder of the journalist Mino Pecorelli, who allegedly was about to reveal Mr Andreotti's ties to Cosa Nostra; the hanging of “God's banker” Roberto Calvi under Blackfriars Bridge in London after the fraudulent collapse of his Vatican-linked bank; the 1978 kidnap and murder by the Red Brigades of Aldo Moro, a Christian Democrat leader who favoured bringing the Communists into government; the killing of Salvo Lima, Mr Andreotti's right-hand man in Sicily; and Mr Andreotti's meeting with the Godfather Toto Riina, during which they were said by Mafia pentiti, or supergrasses, to have exchanged a “kiss of honour”.

Mr Sorrentino said he made Il Divo despite “obstacles” put in his way by “the many powerful people who are still very grateful to Andreotti”. A devout Roman Catholic known variously as Beelzebub, The Black Pope, The Fox, The Hunchback and The Prince of Darkness - as his character observes wryly in the film - Mr Andreotti's career began to falter in the 1990s as Christian Democracy imploded in a series of scandals. His bid to become President failed, and allegations mounted of connections to the illegal P2 masonic lodge and the Mafia. He went on trial for alleged Mafia ties and involvement in the Pecorelli killing, but eventually acquitted. He remains a life senator and an influential figure.

Mr Garrone said he, too, had problems making Gomorra, which is based on a bestselling account of the Naples Mafia by Roberto Saviano. The story shows how Mafia clans operate in areas from drugs to high fashion and the profitable waste-disposal business - the prime cause of the Naples rubbish crisis - but also how it permeates everyday life in a crumbling, once magnificent city.

Camorra members even co-operated in the making of the film, allowing Mr Garrone to use the real Scampia backdrop and advising him on detail. Some Mafiosi had walk-on parts. “I didn't have any problems with the Camorra, even though it was like shooting in a war zone,” the director said. But he added that the darkness of Gomorra and Il Divo was a coincidence. “It's not like we got together and agreed to look at Italy from a certain perspective this year,” he told Hollywood Reporter. “I think good films tend to reflect the current reality.”

In any case, once the initial shock of the films had passed there was a sense that what really matter is that Italian cinema is back. Sandro Bondi, Minister of Culture, who attended the Cannes screenings, said that although Il Divo and Gomorra were uncomfortable to watch, they marked “the renaissance of a strong and engaged Italian cinema, with masterly directors”. The job of the Berlusconi Government, he said, was to tackle the ills they depicted.

Even Mr Andreotti has come to terms with Il Divo, withdrawing his accusation that the film-makers were “malicious blackguards” - and even confessing that he rather likes the scene in which he tells an interviewer that the reality of exercising power is “more complex” than simple judgments about “good and evil” suggest.

And he added: “For anybody in politics, to be ignored is worse than being criticised.”

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