The United Nations World Food Programme (WFP) issued a plea Wednesday for 4.4 million dollars to back its scheme to expand a food aid operation for Somali refugees in Yemen. The agency said in a statement it plans to provide a total of 5,000 tons of food to 43,500 of the most vulnerable Somali refugees in Yemen during the period from February 2008 to January 2010. This is up from 33,000 people the agency was previously helping, according to the statement.