Sienna Miller is urging fellow actresses to boycott film projects which do not offer equal pay for female stars.
The issue of wage equality in Hollywood has been a regular topic in the headlines since emails leaked during the Sony Pictures hacking scandal revealed the female stars of hit drama American Hustle were paid substantially less than the male actors.
Cast member Jennifer Lawrence, whose pay cheque was far smaller than that of co-stars including Bradley Cooper, recently addressed the issue in an open letter in which she blamed herself for not fighting harder for equal pay.
Sienna, who appeared with Cooper in American Sniper and new movie Burnt, has also found herself at the centre of the issue after she quit work on a Broadway play amid a pay dispute, and she has now insisted actresses in Hollywood need to stand up for themselves.
Female stars should "collectively blacklist" projects which do not pay men and women the same, she tells Harper's Bazaar magazine.