Some 1.5 million refugees have fled fighting and famine in South Sudan to neighbouring countries and thousands more are leaving daily, according to the UN refugee agency.

Charlie Yaxley, spokesman for the United Nations High Commissioner for Refugees (UNHCR) in Uganda, said the agency estimated the total number of South Sudanese who have gone to neighbouring countries at 1.5 million, half in Uganda.

"We have already in the first two months of this year received 120,00 new arrivals. If this rate of inflow continues actually that figure for 2017 will be far higher," Yaxley said.

The UNHCR says the refugee crisis is the world’s third largest after Syria’s and Afghanistan’s.