The Hollywood actor Robert De Niro has snubbed the country of his forebears twice in as many days, refusing a top honour from Milan on Thursday and then standing up dignitaries in Rome yesterday.

The two-time Oscar winner flew into Italy for both events, having whipped up a political storm over his portrayal of Italian gangsters, most recently as the voice of the "Godfather" shark in the DreamWorks animation Shark Tale.

Milan's mayor had intended to give De Niro the Golden Ambrosius award, the northern city's highest honour, to show support for the actor many Italians consider one of their own.

But De Niro refused it, provoking fury among officials and the Italian press.

He then failed to turn up at a news conference in Rome about the inclusion of an Italian showcase at New York's Tribeca film festival, which he co-founded.

"He flew straight from Milan to Paris," a spokesman for the Rome provincial government said.

"We don't really know what happened, we haven't had an official explanation."

Local media speculated that the star, who won his first Oscar for his role as a Mafia boss in The Godfather Part II, snubbed the award because of polemics about his portrayal of Italians.

Italy had intended to give De Niro honorary citizenship at the Venice Film Festival in September but delayed it after the Order Sons of Italy in America said he did not deserve it as his gangster roles besmirched their good name.

But many Italians consider their criticism completely unfounded.

"Imbeciles," said Giulia Riccardo, the editor of an Italian travel magazine. "We Italians love De Niro."