A presidential spokesman in South Sudan says the president has appointed his rival, rebel leader Riek Machar, as first vice president in a unity government.Ateny Wek Ateny said Friday that President Salva Kiir expects Machar to travel to Juba, the South Sudanese capital, soon.It was not possible to talk to Machar, who has been living in Ethiopia.Machar and Kiir signed a peace deal in August, although sporadic fighting has continued between government forces and rebels in some parts of the oil-producing East African country.Machar had been Kiir's deputy until July 2013, when his firing triggered a political crisis that later boiled over into a rebellion following a violent split among the security forces in Juba.