U.N. Secretary-General Antonio Guterres on Monday called on the international community to reject the use of hunger as a weapon of war.

U.N. agencies have been warning of life-threatening hunger in Gaza as aid supplies dried up and international pressure has been building for a cease-fire to allow a massive relief operation.

Israel's government, under Prime Minister Benjamin Netanyahu, furiously denies that it is using hunger as a weapon of war, and instead accuses the aid agencies of failing to pick up and distribute aid delivered to Gaza's border crossing points.

"Climate change is disrupting harvests, supply chains, and humanitarian aid. Conflict continues to spread hunger from Gaza to Sudan and beyond," Guterres told a U.N. conference in Ethiopia by video.

"Hunger fuels instability and undermines peace. We must never accept hunger as a weapon of war," the U.N. chief added.