Firth was honoured for his role as a gay professor in Tom Ford's directorial debut A Single Man, while up-and-coming actress Mulligan received the award for her part in An Education, written by Nick Hornby.

He said he was finding award season like an "out of body experience: "It's not unpleasant, I remember from my student days people would pay good money to have an out of body experience, pretty much any way they could, and that's rather what it feels like."

The Single Man star, who also is nominated for an Oscar and a Bafta for his role in the Tom Ford film, admitted awards season was hard work, but that he was delighted to be a part of it.

"It's very difficult. They do work you hard, but they do it in a nice way. It's not a salt mine. You're given every conceivable comfort. You're pushed around and rushed about and all the rest of it," he said.

"It's not a rest for me but it's truly wonderful. I wouldn't wish this away. I mean, I'm nearly 50 and nothing like this has ever happened to me before."

Quentin Tarantino attended the ceremony to pick up its highest honour, the Dilys Powell Award for Excellence in Cinema, for his outstanding contribution to cinema.

The director, screenwriter, producer and actor was celebrated for his classic films such as Reservoir Dogs, Pulp Fiction and Kill Bill, which continue to inspire a generation of young film-makers.

Christoph Waltz, star of Tarantino's latest film Inglourious Basterds, was also honoured at the ceremony, receiving the gong for Actor of the Year.

The Actress of the Year award went to Mo'Nique for her impressive performance as an abusive mother in dark drama Precious.

Gritty British drama Fish Tank received four awards, with Andrea Arnold being named British Director of the Year and Michael Fassbender picking up the British Actor in a Supporting Role award.

Newcomer Katie Jarvis, who landed her debut role as troubled teen Mia in Fish Tank after being discovered arguing with her boyfriend at a train station, received the NSPCC Award for Young British Performer of the Year.

French prison drama A Prophet was named Film of the Year and moving Swedish horror movie Let The Right One In won Foreign Language Film of the Year, while Kathryn Bigelow was given the Director of the Year award for Iraq war drama The Hurt Locker.

Screenwriter of the Year went to Jesse Armstrong, Simon Blackwell, Armando Iannucci and Toni Roche for political satire In The Loop, while Duncan Jones won the Breakthrough British Film-Maker award for sci-fi thriller Moon.

To mark the 30th year of the awards, Francis Ford Coppola's Vietnam war film Apocalypse Now was named the London Film Critics' Circle best film of the last 30 years.

The awards ceremony, hosted this year by Jason Isaacs at the Landmark Hotel, is the only one of its kind that benefits a charity, and has been supporting the NSPCC for 15 years.

/Sky News/