Governments will be held to account over ending sexual violence in war zones, Angelina Jolie has said.
The Hollywood actress and UN special envoy said a new international protocol represented the "beginning of the fight" against the practice.
Speaking to the BBC, she said the protocol meant governments in war zones would no longer be able to say they didn't know how to tackle the issue.
Ms Jolie said women around the world were "united in this fight together".
The actress and UK Foreign Secretary William Hague have been co-chairing the the End Sexual Violence in Conflict global summit, which brings together representatives from more than 100 countries.
The conference, which is in its third day in London, is aiming to create "irreversible momentum against sexual violence in conflict".
Ms Jolie, who has been joined at the summit by her partner, actor Brad Pitt, told the conference: "We are here for the nine-year-old girl in Uganda, kidnapped and forced into sexual slavery.
"We are here for the man in Bosnia, years after rape, still stigmatised, unable to earn enough money to buy bread for his family.
"We are here for all the forgotten, hidden survivors who have been made to feel ashamed or been abandoned.
"And for the children of rape - we want the whole world to hear their stories and understand that this injustice cannot be tolerated, and that sorrow and compassion are not enough."
Ms Jolie said government representatives from around the world would hear the accounts of sexual violence victims from their own countries during the conference.
She said she hoped they would not only be "forced to act, but that they will also deeply want to and be moved and be committed".
The Hollywood star said the new protocol would provide a "manual" for governments to end the crime of sexual violence.
"When our governments say 'well we want to help you, it's wrong but it's a process', we can say it's a process but here's a manual.
"You can't say you don't know and you can't say you don't know how to approach it because it's been done for you by hundreds of experts, including survivors who have decided this is how to handle it in a very comprehensive way," she said.
Mr Hague said it was "critical" that the conference was followed by action.
"This is a subject that the world did not want to talk about for a long time.
"We have moved a long way in the last two years in getting the world to talk about what was a taboo subject, and now we have to follow it with action," he said.
The foreign secretary added that Ms Jolie brings "vast expertise" and described her as "an inspiration".