The Deputy Chairman of the SPLM-IO, Alfred Lado Gore, just arrived at the Juba International Airport.
Mr Gore’s arrival is part of the implementation of the peace agreement.
Gen Ladu was initially scheduled to return to Juba on Sunday, but he failed to show up over what opposition officials say was a technical delay in Nairobi.
He is coming ahead of his boss, Dr Riek Machar, who has confirmed that he will be in Juba on the 18th of April to work with President Salva Kiir in forming a transitional government of national unity.
He was received by the leader of the advance team in Juba, Taban Deng gai, and the SPLM Youth League chairman, Akol Paul Khordit.
General Ladu told a news conference that peace is irreversible.