After one year of hostilities in Sudan, we are appealing for more international engagement to combat sexual violence against women and girls in the country. These barbaric acts, which echo the horrors witnessed in Darfur two decades ago, must spur immediate action.

As members of the Security Council meet this week for the annual open debate on conflict-related sexual violence, we urge them to send an unequivocal message: Under international humanitarian law, civilians in Sudan must be protected and must never be subjected to acts of sexual violence, which constitute war crimes.

Reports of sexual violence reveal the war's disproportionate impact on women and girls. Allegations of rape, forced marriages, sexual slavery, and trafficking of women and girls -- especially in Khartoum, Darfur and Kordofan -- continue to be recorded. Millions of civilians are especially at risk as they flee conflict areas in search of shelter, inside Sudan and in neighbouring countries.

However, the true scale of this crisis remains unseen, a result of severe underreporting due to stigma, fear of reprisals, and a lack of confidence in national institutions.

Without increased political and financial support for the vital work of frontline responders -- especially organisations led by women -- access to life-saving services will only continue to shrink. Fully funding this year's Humanitarian Needs and Response Plan for Sudan -- currently only 10 per cent funded -- will help to support survivors, while bolstering the United Nations' Conflict-Related Sexual Violence Multi-Partner Trust Fund is essential to strengthen the response.

Building on the solidarity demonstrated at last week's International Humanitarian Conference for Sudan and its Neighbours in Paris, we must continue to shore up our support for the people of Sudan -- critically by combating sexual violence in all its forms and ensuring that Sudanese frontline responders stay at the centre of those efforts.