World Bulletin / News Desk
"In the last budget, growth was expected to be 1.3 percent. It is now expected that it will be below 0.5 percent," Zuma said in a speech delivered at an agribusiness conference on Monday night.
He said weak consumer demand and stagnant business investment in the economy continued to be a challenge.
"This is exacerbated by the consistent slow growth of the global economy," Zuma said, adding "lower economic growth means lower revenue and more pressure on the fiscus [Treasury]".
South Africa, which slid into a recession in June, has been struggling to address its slow economic growth.
Experts say political uncertainty, such as sacking of respected Finance Minister Pravin Gordhan four months ago led to tumbling of markets and affected investor confidence.
Africa's most advanced economy is also currently faced with a credit downgrade.
However, in his speech, Zuma expressed optimism to turn around the current situation with determination, unity and willingness of all sectors to pull themselves together.
He said his government had announced some actions to improve the implementation of a number of important existing economic policy interventions.