The Margaret Thatcher biopic, The Iron Lady, has premiered in London with star Meryl Streep wowing the crowds on a blue carpet, instead of the traditional red, in honour of the Conservative colour.

The film opened at the British Film Institute on London's South Bank.

Streep's performance as Thatcher, who was prime minister from 1979 to 1990, won several accolades at a number of film festivals and she has been tipped for an Oscar.

"It would be great, because the secret of the nomination is that it comes from the actors and actors are the ones who know what you go through. So it would be amazing," she told the Telegraph.

The film, directed by Phyllida Lloyd and written by Abi Morgan, shows the Conservative leader living a lonely life as she grows older.

The film has received a mixed response from critics and Thatcher's family members were not present at the premiere, although they were invited.

Despite inclement weather, enthusiastic fans gathered outside the venue to catch a glimpse of Streep, who wore a blue poncho style jacket in emulation of Thatcher's penchant for blue outfits.

Her co-stars in the film, Jim Broadbent, Olivia Colman, Richard E Grant, Anthony Head, Harry Lloyd and Alexandra Roach, were also in attendance.