Parts of Gaza are officially experiencing a “man-made” famine, according to a Friday report by a United Nations-backed initiative, which added that the situation is expected to worsen after months of relentless conflict.

The United Nations officially declared a famine in Gaza on Friday, blaming "systematic obstruction" of aid by Israel during more than 22 months of war.

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.