At 1659 GMT, the rand weakened 0.56% to 15.1550 per dollar, compared to its close of 15.0700 on Friday.
In the equities market, pharmacy and healthcare retailer Clicks Group topped the gainers after revising its earnings forecast range upwards, pushing its shares up 13.54% to 247.75 rand.
The Johannesburg All-Share index closed 1.34% higher at 54,714 points, while the Top-40 index climbed 1.38% to 48,635 points.
In fixed income, the yield on the benchmark government due in 2026 was up by 3 basis point to 8.215%.
Clicks now expects that diluted headline earnings per share for the year ended August 1, will increase by between 15% and 18%, compared to the previous forecast of between 10% and 15%.
Petrochemicals company Sasol was the second biggest gainer on the blue-chip index, rising 6.47% to 268.52 as it benefited from rising oil prices. The United States and China are set to meet for trade negotiations in Washington on October 10-11, although latest reports suggest Beijing may be looking to restrict the scope of any deal.