The former governor of Nigeria's central bank has spoken exclusively to Al Jazeera following his sacking last week by President Goodluck Jonathan. Sanusi Lamido Sanusi was fired after he revealed that around $20bn in public money from oil sales is missing. Sanusi said the money disappeared in just the last 19 months. The money was supposed to be given to the Central Bank by the state oil company. He said he would not be surprised if he is jailed for speaking out. Al Jazeera's Yvonne Ndege reports from Lagos.