Oscar-winning actress Meryl Streep has said it is "infuriating" that the film-making industry continues to be male-dominated.
The 66-year-old star, who portrays political activist Emmeline Pankhurst in her latest film Suffragette, called for more women to be included in the decision-making processes, as the BFI London Film Festival kicked off today.
Streep said: "A huge part of this business is driven by buzz. I wanted to find out what controls buzz. In the United States, when people go to find a movie to watch, they go to a website called Rotten Tomatoes.
"So I went deep, deep, deep into Rotten Tomatoes and I counted the contributors - the critics, bloggers and writers who satisfy the strict criteria to be a critic. Of those people who are allowed to rate on the 'tomato' meter, there are 168 women. If there were 168 men, that would be balanced. If there were 268 men, that would be unfair but expected."
She continued: "Actually, there are 760 men who can rate the tomato meter. If that meter is slanted to one type of taste, that drives the box office."
Streep, who has received 19 Oscar nominations and won three times, also checked the film critics' organisations in America, where she discovered there were 37 men in the New York Film Critics Circle, compared with just two women.
"It is infuriating because people accept it as received wisdom ... It isn't fair. We need inclusion," she said.
The New Jersey-born actress, who has played former British prime minister Margaret Thatcher in The Iron Lady and has starred in movies such as The Devil Wears Prada, Out Of Africa and Mamma Mia!, has taken steps for change. She wrote to all 535 members of the US Congress calling for the introduction of new equality laws, and launched a screenwriting workshop for female writers over the age of 40.
Suffragette, directed by Sarah Gavron and written by The Iron Lady and The Hour's Abi Morgan, stars Carey Mulligan as aspiring activist Maud Watts, alongside a star-studded cast including Helena Bonham Carter, Anne-Marie Duff, Ben Whishaw and Brendan Gleeson.
Morgan - who worked on the film for six years with Gavron - admitted it was "hard" getting it made, because "it's led by a female ensemble, and it's not funny or romantic".
The period drama, which tells the story of the British women's suffrage movement of the late 19th and early 20th century, will premiere tonight at London's Leicester Square.
Helen Pankhurst, the great-granddaughter of suffragette Emmeline, and Laura Pankhurst - Emmeline's great-great-granddaughter - will join the cast at the gala screening, which comes ahead of the film's release on October 12.
:: The London Film Festival runs from October 7 to 18, with Steve Jobs closing the 10-day event.