LISTEN: Deputy finance minister calls for 'exceptional leadership' within govt

Jonas says the middle class and poor will also be affected - as the cost of borrowing would double, or even triple.

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"That has huge implications - on our social spending, on some of the problems we're driving  as a country. So this is a matter for all South Africans. I know that we have no choice but to be optimistic. We need deliberate and urgent actions amongst the relevant ministries to remain constraints to problems," he said.

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Jonas delivered the opening address at the Association of Black Securities and Investment Professionals' annual conference in Sandton this morning. He says South Africa needs strong leadership to grow the economy.