Story highlights Yemen, South Sudan, Somalia and northeast Nigeria face starvation

"Without ... global efforts, people will simply starve to death," UN says

(CNN) Somalia and three other countries desperately need aid to save more than 20 million people from starvation and diseases, the United Nations said.

The UN pleaded with the world to come to the rescue of Yemen, South Sudan, Somalia and northeast Nigeria.

"We stand at a critical point in history. Already at the beginning of the year we are facing the largest humanitarian crisis since the creation of the UN," UN humanitarian chief Stephen O'Brien said Friday.

"Now, more than 20 million people across four countries face starvation and famine. Without collective and coordinated global efforts, people will simply starve to death. Many more will suffer and die from disease."

The UN was founded in 1945.

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