ADDIS ABABA (Reuters) - South Sudanese rebel leader Riek Machar's demand for the release of detainees remains a stumbling block to a ceasefire deal aimed at halting violence in the world's youngest state, a U.S. envoy said on Sunday.
More than three weeks of fighting, often along ethnic faultlines, has pitted President Salva Kiir's SPLA government forces against rebels loyal to former vice president Machar and has brought the oil-exporting nation close to civil war.
