A UN-backed report warns that Gaza is facing a man-made famine affecting hundreds of thousands, while Israel prepares for a major offensive.

The White House has not commented on a report finding famine in Gaza. Analysts say that absent U.S. pressure, Israel is unlikely to change course.

An immediate ceasefire is critical to allow a large-scale humanitarian response that can save lives, the UN said.

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.

An announcement of famine — as has now happened regarding Gaza — is a complicated decision. Here's what must be considered before such a declaration is made.

"An entire population is being pushed into starvation, destitution, and death,” said Belgium's Deputy Prime Minister.