Meryl Streep's portrayal of Margaret Thatcher is expected to earn her another Oscar nomination when they are announced later today.

The actress, who has won two Oscars in her career, is strongly tipped to pick up the Best Actress statuette for her performance as the former prime minister in The Iron Lady.

But she could face competition from Michelle Williams for her role in My Week With Marilyn, in which she played Hollywood legend Marilyn Monroe, and Viola Davis, who played a put-upon maid in the deep south-set The Help.

Tilda Swinton and Carey Mulligan are likely to carry the flag for UK actresses for their performances in We Need To Talk About Kevin and Shame respectively.

Shame, Steve McQueen's study of sex addiction, could also win a nomination for his leading man, German-Irish actor Michael Fassbender.

The surprise hit of the year, The Artist, a French tribute to the silent film era, could sweep the board.

It is expected to be nominated for Best Film and its leading man, Jean Dujardin, should get a Best Actor nod.

The critics have also praised Newcastle-born actress Janet McTeer for her role in Glenn Close's gender bending drama Albert Nobbs.

Kenneth Branagh's role as Sir Laurence Olivier in My Week With Marilyn, could also see him among the nominations.

Gary Oldman is an outside bet for his performance as secret agent George Smiley in Tinker, Tailor, Soldier, Spy.

Other big names in the running for a nomination are George Clooney for The Descendants, Brad Pitt for Moneyball and Leonardo DiCaprio for J Edgar - Clint Eastwood's biopic of FBI boss J Edgar Hoover.

Steven Spielberg could get a nod for War Horse, based on the National Theatre play inspired by Michael Morpurgo's novel, when the nominations are announced by actress Jennifer Lawrence and Academy of Motion Picture Arts and Sciences President Tom Sherak.

They will reveal 10 of the 24 categories for the 84th Academy Awards.

The Oscars ceremony, hosted by Billy Crystal, takes place on Sunday February 26 at the Kodak Theatre in Hollywood.

Crystal, who has hosted the ceremony eight times already, stepped in after Eddie Murphy pulled out.