Mike Leigh's controversial film Vera Drake has scooped a double triumph at the 61st Venice Film Festival.
Imelda Staunton won the best actress award for Vera Drake
The film, which is about abortion, unexpectedly took the Golden Lion prize for best film.
And British actress Imelda Staunton won the best actress award for her role as a cleaning lady who secretly carries out abortions in the low-budget film.
The jury announced the winners during the final evening of the 11-day festival on Saturday.
Accepting the Coppa Volpi prize, Staunton said: "I want to thank the tireless jury for embracing and honouring this film which I'm so proud to be in, because it deals with a
complex subject with such compassion."
Vera Drake beat 21 other films to win the Golden Lion, which was awarded at a gala ceremony in Venice's restored La Fenice opera house.
Leigh thanked the organisers of this year's Cannes Film Festival "for rejecting this film so we might be here this evening".
"Thank you Venice."
He also thanked the jury, which included Dame Helen Mirren, Scarlett Johansson, Spike Lee and British director John Boorman, for their "excellent decision" and the UK Film Council for its support.
"All film making is tough and Vera Drake was no exception," Leigh said.
"In a cynical world it is a wonderful thing and most reassuring when low budget, serious, committed, independent, European films are recognised and encouraged in this way and helped to reach their audience."
Spanish actor Javier Bardem took the best actor award for his portrayal of a paralysed man who wants to kill himself in Alejandro Amenabar's Mar Adentro.
Bardem previously won the best actor award at the 2000 Venice festival for Julian Schnabel's Before Night Falls, for which he was also nominated for an Academy Award for best actor in a leading role.
Thousands watched the screening of Shark Tale in St Mark's Square
Stars including Tom Hanks, Nicole Kidman, Tom Cruise, Robert De Niro and Angelina Jolie have all attended this year's festival.
New festival director Marco Muller's gamble on Hollywood glamour to bring in the crowds paid off, with numbers up by one-third.
But the move has brought its share of problems and criticism.
Delays and organisational chaos has lead to Muller promising a more streamlined festival next year.
Al Pacino was among those left without a seat at the premiere of his own film, The Merchant of Venice, after a computer glitch printed hundreds of extra tickets.
The mistake caused knock-on delays across the festival.
The premiere of Finding Neverland, starring Johnny Depp and Kate Winslet, began more than two hours late as a result.
Harvey Weinstein of Miramax films eventually introduced the screening in the early hours of the morning, saying: "Welcome to the breakfast screening of Finding Neverland. This morning Muller will be serving the croissants and I'll be teaching
him the meaning of timing."
Scandal also dogged the festival in the form of Nicole Kidman's relationship with a child in Birth.
But there were also a number of high-profile premieres.
Director Steven Spielberg joined star of The Terminal, Tom Hanks, at the European premiere early in the festival.
And thousands of people watched the premiere of animated film Shark Tale on inflatable screens in St Mark's Square on Friday night.
Will Smith, who voices Oscar the fish, said the event was "up there with the No 1 premiere of all time. It doesn't get much better than this".