Stocks fell with investment holding firm PSG Group among the decliners after sources told Reuters Steinhoff is considering PSG and KAP Industrial stake sales to lift liquidity.
At 1600 GMT, the rand traded at 13.6900 per dollar, 0.7 percent weaker than its close on Monday.
Traders said the currency was expected to trade in ranges ahead of the ANC conference which kicks of on Saturday. The party will crown a new leader to succeed President Jacob Zuma, who can remain president of the country until 2019.
The two front-runners to succeed Zuma are Deputy President Cyril Ramaphosa and former chair of the African Union Nkosazana Dlamini-Zuma.
"Rand trade might be boring now but it is expected to be explosive over the weekend," Rand Merchant Bank analyst John Cairns wrote in a note.
"One-week implied volatility on USD/ZAR has jumped to over 30 percent, implying the market now puts over a 50 percent probability of a 5 percent move in the rand over the week, that is to under 13.00 or over 14.30."
Globally, investors expect the US Federal Reserve to hike interest rates at its two-day policy meeting that ends on Wednesday. Higher US rates often drain capital away from higher-yielding, but riskier emerging markets, weighing on their currencies.
In fixed income, the yield for the benchmark government bond due in 2026 rose 5 basis points to 9.275 percent, reflecting weaker bond prices.
On the bourse, the benchmark Top-40 index declined 0.77 percent to 51,312 points, while the broader All-share index fell 0.82 percent to 57,523 points.
PSG, in which Steinhoff owns about 25 percent, closed 3.25 percent weak at 242.30 rand after sources said that Steinhoff is considering selling stakes worth a combined $1.4 billion in it and KAP Industrial to help plug a liquidity gap at the retailer.
"We could see some selling pressure coming in, guys (Steinhoff) have to sell some shares to raise money," said BP Bernstein trader Vasili Girasis.
"We've got the ANC conference coming up so guys are feeling a bit uncertain about the outcome of that. We have that rollercoaster to ride from now until then."
A broad base retreat was evident in financials, materials and retail as investors positioned themselves ahead of the ANC conference. The financial index fell 0.51 percent, while the retail index declined 0.93 percent.