The United Nations launched on Monday a campaign to combat violence against women and girls, calling it a global scourge affecting a third of the world's female population.

"At least one out of every three women is likely to be beaten, coerced into sex or otherwise abused in her lifetime," U.N. Secretary-General Ban Ki-moon told a meeting of the U.N. Commission on the Status of Women.

"Through the practice of prenatal sex selection, countless others are denied the right even to exist," he said.

In India, female infanticide and the deliberate abortion of female fetuses are illegal but still prevalent as boys are traditionally preferred to girls as breadwinners, and families have to pay huge dowries for their daughters' marriage.

Ban said the weapons of war in the 21st century included rape and other forms of sexual violence and the kidnapping of children who are forced to be soldiers or abused as sex slaves.

Ban urged women's groups, men across the globe, the private sector and U.N. member states to help the new initiative succeed. But he added that every country will have to adopt its own measures to address violence against women.

The campaign will run until 2015, which is also the deadline for the U.N. Millennium Development Goals aimed at halving poverty.