In a television interview, South Africa's President Jacob Zuma has hit out at critics for not saying why they want rid of him.

"In the process of this discussion, it was clear that people are saying 'Zuma must go'. My problem is that... they themselves never provided a reason," Mr Zuma told South African broadcaster SABC.

Mr Zuma's party, the African National Congress, has given him until the end of the day to resign.