South Sudan, which broke away from the north only last month, has replaced its central bank governor with his deputy, the outgoing bank chief said on Tuesday.

The central bank of Africa's newest nation has been selling dollars to try to stop a slide in its currency, the pound.

"My deputy has now been appointed (as governor), Kornelio Koriom," Elijah Malok told Reuters by telephone. He did not say why he was standing down or give any other details.

As well as his role as Malok's deputy, Koriom was also chairman of the South Sudan Currency Conversion Committee.

Malok previously headed the Bank of Southern Sudan, which was linked to the Khartoum-based Central Bank of Sudan until southern independence.

Malok said last week that the southern central bank had enough reserves to pay for the basic needs of the state for a "few months", even if it does not receive oil revenues.

The war-ravaged and underdeveloped new state has been trying to build up efficient institutions and develop an economy that is at present totally dependent on oil.