Updated

An official for a U.N. aid organization says Africa faces the world's largest humanitarian crisis since 1945, with more than 20 million people facing starvation in three countries: South Sudan, Somalia and Nigeria, as well as nearby Yemen.

David Orr, WFP's Africa spokesman, responding to questions Thursday about U.S. President Donald Trump's proposal to cut $10 billion in foreign aid, said that a cut in funding to humanitarian agencies working in famine-affected areas will cause untold suffering.

The U.S. is WFP's largest donor and was a founder of the organization. Orr said that last year the U.S. contributed more than $2 billion, representing about 24 percent of WFP's total budget.

He said U.N. operations in South Sudan, Somalia, Yemen and Nigeria will require more than $5.6 billion this year.