Israel has called the United Nations' declaration of famine in parts of Gaza an "outright lie," but multiple U.N. bodies, more than 100 humanitarian groups, and several of Israel's own allies have warned for months that the war and Israel's restrictions of food into Gaza are causing starvation among civilians.

The United Nations officially declared a famine in Gaza on Friday, blaming "systematic obstruction of aid" by Israel, hours after Defence Minister Israel Katz threatened to destroy the territory's largest city.

At least half a million people in the enclave were facing the most severe conditions measured by U.N.-backed international experts: starvation, acute malnutrition and death.