A low budget gay cowboy movie and a maverick star-turned-director hailed as the new Warren Beatty were the big winners at today's Oscar nominations in Los Angeles.

Heading a list of nominees guaranteed to infuriate the so-called red states, George Clooney cemented his status as one of Hollywood's most influential players with three Oscar nominations.

Clooney won best director and original screenplay nominations for his classic liberal movie Good Night, and Good Luck and a supporting actor nomination for his role in oil industry thriller Syriana.

The gay cowboy movie Brokeback Mountain received eight nominations for the 78th Academy Awards, to be held at the Kodak Theatre in Hollywood on March 5, including best picture, best director and best actor for Heath Ledger. The news is likely to make devout film-goers in Bible Belt America choke on their breakfast.

Widely expected to dominate Oscar nominations after winning four Golden Globes, Brokeback Mountain also received best supporting actor and actress nominees for Jake Gyllenhaal and Michelle Williams. The film cost $14 million to make and has already taken more than $61 million despite a limited release in conservative American states.

Best picture nominations also went to biopic Capote, race drama Crash, Steven Spielberg's lumbering political thriller Munich and McCarthy-era drama Good Night And Good Luck.

But despite best actor and actress nominations for its stars Joaquin Phoenix and Reese Witherspoon, there was disappointment for Walk the Line which was not included in the nominees for best picture and received only five nominations.

Brokeback's director Ang Lee was nominated for best director alongside Clooney, Steven Spielberg and first-time directors Paul Haggis and Bennett Miller.

Britain was well-represented on the list, with a trio of actresses nominated for honours. Keira Knightley and Dame Judi Dench will go head to head for the best actress award. Knightley - a surprise inclusion in the list - is nominated for her role in Pride and Prejudice, Dame Judi for her performance in Mrs Henderson Presents.

Dame Judi said: "It’s absolutely wonderful. I’m absolutely thrilled. I’m so happy to be nominated for something I loved filming every single day."

There was also good news for Britain's Golden Globe winner Rachel Weisz, nominated in the best supporting actress category for her role as Tessa Quayle in The Constant Gardener. With best supporting actress awards at the Golden Globes and Screen Actors Guild (SAG) under her belt, Weisz, 34, was regarded as an early favourite.

Later, Weisz said she was "thrilled" to be nominated for an Oscar. Speaking from Los Angeles, She said: "It’s incredibly exciting and it is wonderful as a Brit to be honoured in this arena.

"The category is full of very talented actresses. I have seen all of the films and they are all great performances. I’m just happy that the film and the issues raised in it are being recognised."

The shortlist was announced live from Los Angeles at 5.30am (1330GMT). Knightley and Dench face stiff competition from former winner Charlize Theron, Walk the Line star Reese Witherspoon and Desperate Houswives actress Felicity Huffman, who is nominated for her role as a man awaiting a sex-change operation in the film Transamerica.

This is the first Oscar nomination for 20-year-old Knightley and the fourth for Dame Judi, 71, who won best supporting actress in 1999 for Shakespeare In Love.

After the loss of much of his studio in a huge fire last year, Aardman Animation's Nick Park was delighted at the nomination for The Curse of the Were-Rabbit, his first full-length Wallace and Gromit film. Also nominated in that category are Corpse Bride and Howl's Moving Castle.

Park said that he and co-director Steve Box had been shocked and surprised after their film was named on the short list for Best Animated Feature. Speaking from Heathrow airport, Park said: "We’re both absolutely delighted. We’re over the moon."

Arthur Sheriff, a spokesman for Aardman Animations, the studio behind the hit animations, said: "This is the fifth time Nick has been nominated for an Academy Award and puts him in the running for his fourth Oscar. It’s an amazing achievement for Steve and Nick and for the UK as a whole."

Former Oscar winner Mira Sorvino joined the president of the Academy of Motion Pictures to reveal the nominees.

This year's awards will be hosted by comedian Jon Stewart, presenter of The Daily Show. Robert Altman, a US director whose films include M*A*S*H and The Player, will receive an honorary Oscar.

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