UNITED NATIONS, Dec. 18 (Xinhua) -- UN humanitarians on Wednesday reported widespread hostilities in Sudan, including shelling and airstrikes on civilian areas of Darfur and Khartoum, which inflicted significant casualties and destruction.

The UN Office for the Coordination of Humanitarian Affairs (OCHA) said Clementine Nkweta-Salami, the resident humanitarian coordinator in Sudan, condemned the attacks over the past week.

"Hostilities are widespread and have been reported in urban areas of Al Fasher, Al Kuma, Kabkabiya and Kutum in North Darfur, as well as Nyala in South Darfur, and in Greater Khartoum," OCHA said. "Significant civilian casualties have been reported, along with the destruction of homes, markets and medical facilities."

The coordinator said the wave of violence against civilians underscores the need for immediate de-escalation of the fighting between two military factions and their allies. She warned that armed combatants operating in and around populated areas and camps for conflict-displaced people pose direct threats to residents and are blocking the delivery of life-saving assistance.

Nkweta-Salami said that civilians and civilian infrastructure, including hospitals, must be spared the effects of hostilities.

"The principles of distinction, proportionality and precautions in attacks must be respected at all times," she said.

The coordinator said that after 20 months of fighting, the ever-rising toll of the dead and injured is unacceptable, and international humanitarian law must be respected.

"I call for an immediate cessation of hostilities and safe passage for civilians wishing to flee to destinations of their choice," she said. ■