United Nations -- UN Secretary General Ban Ki-moon on Thursday urged world leaders to end violence against women in their countries, in a speech ahead of International Women's Day.

"Violence against women cannot be tolerated, in any form, in any context, in any circumstances, by any political leader or by any government," said Ban.

"We must unite. The time for change is now. Only by standing together and speaking out can we make a difference," he added, ahead of Sunday's events to mark women's economic, political and social achievements.

The United Nations has also launched a database to document violence against women and follow global efforts to combat the violence.

Ban revealed that around the world, one woman in five has been a victim of rape or attempted rape, and that in some countries one woman in three has been beaten or subjected to some kind of violent act.

"Violence against women is an abomination. I'd like to call it a crime against humanity," he told ministers from over 50 countries and more than 1,000 representatives of women's groups attending the annual UN Commission on the Status of Women from March 2 to 13. "This is alarming, this must stop."

He singled out testimonies he had heard from women victims of the conflict in the Democratic Republic of Congo (DRC), saying: "I was shocked ... I was saddened almost beyond expression. I was also very, very angry."

Ban has just returned from a visit to the country following unrest that erupted in August, sparking a humanitarian crisis and displacing more than a quarter of a million people.

He visited a clinic where women were being treated, and also held talks with Congolese President Joseph Kabila.

"I spoke forcefully about this when I met President Kabila of DRC ... Eighty percent of these sexual attacks are perpetrated by the other armed groups, the rebels," Ban said over sustained applause. "But I told President Kabila, 'that isn’t an excuse.' As the leader of a country, the sovereign leader of a sovereign country, whenever sexual violence may happen, he must be responsible."

Ban's deputy Asha-Rose Migiro, a former Tanzanian minister for gender equality, later unveiled a database to document "the extent, nature and consequences of all forms of violence against women," as well as "the impact and effectiveness of policies and programs for combating such violence."

She said this tool would provide individuals and officials useful information to help improve laws, plans of action, policies and services targeting the violence.

UN Special Rapporteur on Violence Against Women Yakin Erturk expressed an optimistic outlook.

"Women around the world are no longer fearful of speaking out against the violence they encounter," she said. "The silence about violence against women has been broken ... It's an initial step, but it's a prerequisite for us to respond to that violence. I think women in all parts of the world now realize that violence is not their fate."

The theme of this year's International Women's Day on March 8 is "women and men united to end violence against women and girls."

Herve Couturier/AFP/Expatica