Film director Gurinder Chadha has criticised the film industry for its lack of support towards "women and people of colour" and urged "rigorous intervention".
The Bend It Like Beckham creator also voiced her concern that she is still the only Asian woman making feature films in Britain after 25 years in the business.
She said: "I made my first feature 25 years ago, Bhaji On The Beach, for Film 4. I was the first Asian woman to make a feature film in Britain. I'm still the only Asian woman.
"That is indicative of just how hard it is to get out there, particularly for women and particularly for people of colour."
She went on: "When people see women directors, stories from a women's perspective or from people of colour, people have to shift into their head space and a lot of people aren't used to doing that because the whole world is geared towards the way blokes think.
"I think that unless we have a really rigorous intervention, I really can't see things changing."
Kathryn Bigelow is the only woman to date to win the best director Oscar, for The Hurt Locker in 2009, and no black director has ever won the prize.
The first time a non-white filmmaker took the prize was when Ang Lee was honoured for Brokeback Mountain in 2005. He also won again for Life Of Pi in 2012.
Seven years in the making, Chadha's latest film, Viceroy's House, was inspired by her 2006 trip to Pakistan for an episode of the BBC ancestral programme Who Do You Think You Are?
Brought up in London, but with family in the Punjab, the director felt driven to tell what she felt was the untold collective history of Britain, India and Pakistan.
Told from the perspective of the great grandson of Queen Victoria, Lord Louis Mountbatten, it tells the story of the final months of British rule in India following the partition of the country in 1947.
Viceroy's House, staring Hugh Bonneville, Gillian Anderson and Michael Gambon, is released in UK cinemas from Friday 3 March.