A UN official on Tuesday called for an end to the use of explosive weapons in urban areas and attacks on medical care facilities while stressing the importance of holding war crimes accountable.

When explosive weapons are used in urban areas, almost 90 percent of the people killed are civilians. That compares with less than 20 percent when these weapons are used in rural areas, said UN Undersecretary-General for Humanitarian Affairs Mark Lowcock during a Security Council open debate on the protection of civilians in armed conflict.

These weapons also inflict a devastating toll on essential civilian infrastructure, he added, calling on fighting parties to change their choice of weapons and tactics.

Medical personnel, transportation and facilities continue to come under attack. Doctors and nurses are threatened, abducted and killed. Facilities and medical transport systems, including ambulances, are destroyed and damaged. The wounded and sick are denied access to care, said Lowcock.

Last year, attacks on health care facilities in 22 conflict-affected countries killed 182 health workers, with the highest numbers losing their lives in Burkina Faso, the Democratic Republic of the Congo, Somalia and Syria, he said.

Lowcock called on states to ensure that military targets are far from medical facilities; take precautions, including through the issuing of warnings on military action; refrain from using medical facilities to support the military effort; ensure that military rules of engagement respect international humanitarian law.

"States can improve the training of their forces, they can modernize policies to avoid civilian harm, they can adopt a more consistent approach to tracking and recording civilian casualties, they can investigate incidents when they occur, and they can hold those guilty of violations to account," he said.

Lowcock emphasized the crucial importance of accountability. "If war crimes go unpunished, things will get worse. Accountability for violations must be systematic and universal, because what is not punished is encouraged," he said.