War rape summit to begin in London
A declaration of commitment to end sexual violence in conflict has been endorsed by 141 countries.
A four-day summit on sexual violence in war is to begin in London, hosted by UK Foreign Secretary William Hague and UN Special Envoy Angelina Jolie.
The event is the result of an intense two-year campaign to raise awareness.
Hague said rape was one of the "great mass crimes" of modern times.
He has called on the 140 nations attending the summit to write action against sexual violence into their army training.
Representatives from governments and NGOs from around the world will join the conference at the ExCel Centre in London.
Nations taking part in the summit included Bosnia, the Democratic Republic of Congo and Somalia - countries where sexual violence had happened "on a vast scale", Hague said.
Hague cited the estimated 50,000 women who were raped in Bosnia two decades ago, virtually none of whom have received justice.
"What we're trying to do this week is agree a new international protocol that sets standards for documenting and investigating these crimes, so that people know that in many cases justice will be done and these crimes can't be committed with impunity," he said on Tuesday morning.
In the two years since Mr Hague and Ms Jolie launched their campaign, a Declaration of Commitment to End Sexual Violence in Conflict has been endorsed by 141 countries.
But the aim now was to take concrete steps, including improving the investigation and documentation of sexual violence and providing more help to survivors, William Hague said.
He added that the issue had been a "taboo" for too long, and that it was time to get rid of the "stigma and shame attached to it".