WFP says ending hunger by 2030 would cost just $93 billion a year — less than one per cent of the $21.9 trillion spent on military budgets over the past decade.
Ms McCain said that droughts had destroyed harvests in areas where 70 per cent of the population depended on agriculture for survival.
UN food security agencies have warned that South Sudan faces a severe humanitarian crisis.
No fewer than 2.6 million people have been displaced since the start of the conflict on April 15 in Sudan.
WFP said the UN food agency would lift a suspension of its aid mission in Sudan as the crisis in the country worsens amid ongoing violence.
