The honors added to growing momentum for the sentimental throwback to the "pre-talkie" Hollywood era after it won three Golden Globes and was the most-nominated movie for Britain's BAFTA awards.

It is widely expected to be among the frontrunners for major honors at the Oscars when nominations are announced on Tuesday.

Lead actor Jean Dujardin and director Michel Hazanavicius were both in London to receive their awards.

Also taking home three prizes was Iranian drama "A Separation", winning best foreign language film, best screenwriter for Asghar Farhadi and best supporting actress for Sareh Bayat.

The examination of the class divide in contemporary Iran was an instant hit with critics and audiences when it was first launched at the Berlin film festival a year ago.

It went on to win the top prize there, the Golden Bear.

Meryl Streep continued her march towards Oscars glory with another award for her portrayal of former British Prime Minister Margaret Thatcher in "The Iron Lady".

The only surprise was that she shared the best actress honor with Anna Paquin for her performance in "Margaret".

Olivia Colman was named British actress of the year for her performances in "The Iron Lady" and "Tyrannosaur", while Kenneth Branagh won best supporting actor for his turn as Laurence Olivier in "My Week With Marilyn".

Michael Fassbender collected the British actor of the year award for his performances in "A Dangerous Method" and "Shame".

Director Lynne Ramsay was at the ceremony to receive The Attenborough Award: British Film of the Year for "We Need to Talk About Kevin". Asif Kapadia won best documentary for "Senna".

(Reporting by Mike Collett-White, editing by Christine Kearney)

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