The United Nations is warning that the world is facing its worst humanitarian crisis since the organization was founded in 1945.

Currently, more than 20 million people across Yemen, Somalia, South Sudan and northeastern Nigeria, are facing disease, starvation and famine.

Without collective and coordinated global efforts, the UN says people “will simply starve to death.”

Jamie McIntosh, World Vision’s head of international programs, who just returned to Toronto from Somalia, told CTV News Channel Saturday that the situation on the ground is “pretty devastating.”

The humanitarian community is intervening, he added, but “our resources are dwindling.”

McIntosh added: “We need reinforcement supplies to come, so that we can keep people alive.”

Aid organizations are trying to “speed up” the delivery of resources in to the countries to provide clean water, nutrition, medical supplies and hygiene training, with the goal of getting people back on their feet and children back into school.

Several organizations are raising emergency response funds to combat the crisis, including: