The Screen Actors' Guild has held its own Hollywood bonanza in the run-up to the Academy Awards, throwing up some surprises to keep Oscar-watchers guessing.

As expected, Russell Crowe took the best actor award for his portrayal of schizophrenic mathematics genius John Forbes Nash in the film A Beautiful Mind.

Berry caused the main upset of the awards

But Halle Berry - who plays a down-and-out waitress in the rural south in Monster's Ball - surprised everyone by beating Sissy Spacek to take best actress.

And the guild gave no clues to the possible winner of the Oscar for best picture, choosing the mainly British cast of Robert Altman's film Gosford Park for its top performers award.

The SAGs are the last major awards before the Oscars and are considered a good indication of which stars will go on to win golden statuettes.

But the five Oscar nominations for best picture have now all won major awards and the contest is considered wide open.

Russell Crowe said he was pleased that a film about mental illness had received such recognition.

Helen Mirren shows her delight

"This is a great job, and I want to encourage every one of you in this room to give everything you can to the story," he said at the ceremony.

"God bless narrative. God bless originality."

Crowe won the Oscar for best actor last year for his role in Gladiator.

If he wins again on 24 March he will become the first actor to win two straight Oscars in a row since Tom Hanks, who won for Philadelphia in 1993 and Forrest Gump in 1994.

Best supporting actor went to Sir Ian McKellen, for his performance as Gandalf in Lord of the Rings: The Fellowship of the Ring.

Helen Mirren fought off competition from Dame Judi Dench and eight-year-old Dakota Fanning - who starred in I Am Sam and is the youngest SAG nominee to date - to win best supporting actress for her part below the stairs in Gosford Park.

Ben Kingsley won for Anne Frank

In the television awards, The West Wing once again dominated proceedings.

The programme won best ensemble award with Martin Sheen - who plays the US president - winning the best actor gong and Allison Janney - who plays a White House press secretary - winning the best actress category.

Sean Hayes and Megan Mullally were named best actor and actress in a comedy series for their roles in Will and Grace while Sex and the City won the ensemble category.

British actor Sir Ben Kingsley won the made-for-TV male actor award with Judy Davis winning the corresponding best female category.