Yemen is in a state of political unrest, which is creating food prices and unemployment to skyrocket. The situation has been exacerbated by the decision by some international aid agencies to leave the country due to security fears. Some, like the World Bank have returned. Others such as Oxfam are urging other Arab nations to donate aid to Yemen.
For more see: Finn, Tom and Nour Merza. "Political unrest deepens plight of Yemen children," Reuters, 15 February 2012.