South Africa's rand reached a new record low against the dollar on Monday after another sharp fall in Chinese shares, while the weaker currency weakened financials and retailers on the stock exchange.

At 1554 GMT the rand fell 1.03 percent at 14.0175 against the dollar compared with its Friday close of 13.8750.

Trading was lighter than usual with U.S markets closed for the Labour Day Public holiday, while market watchers shifted their attention back to Asian markets as stocks weakened, led by a slide in China.

"As long as the Chinese economy remains under pressure, so are we," said Ion de Vleeschauwer a forex chief dealer at Bidvest Bank.

China's foreign exchange reserves posted their biggest monthly fall in August reflecting Beijing's attempts to halt a slide in the yuan and stabilise financial markets, but trimmed 2014 growth figures on Monday.

China's policymakers and regulators promised deeper financial market reforms during the G20 meeting but analysts said the remarks did nothing but make investors more nervous as this could mean the economy is in a far worse state than expected.

Recent rand slide has brought concerns of too little Reserve Bank intervention with Governor Lesetja Kganyago saying on Saturday a further fall in the rand currency is not necessarily a bad thing.

"I suppose the market knew it but to hear them confirm it, makes it more vulnerable as it looks like they're not too concerned about it," said de Vleeschauwer.

On the back of a weaker rand, yields on government bonds rose across the curve with the benchmark 2026 issue up 5 basis points at 8.615 percent.

On the bourse, the benchmark Top-40 index ended 0.36 percent lower at 43,389 points and the All-share index, the broadest measure of the South African stock market performance, lost 0.52 percent to 48,847 points.

Barclays Africa fared the worst among the JSE's blue-chips, tumbling 5.13 percent to 166 rand, leading financials lower.

Africa's largest grocer, Shoprite, fell 5 percent to 166 rand, the second-biggest faller on the day.

Fashion retailer The Foschini Group shed 3.29 percent to 147 rand, while its larger rival Mr Price slipped 3.11 percent to 202.99 rand.

"Because they are big importers, South Africa's retailers tend to weaken if the rand falls," said Petri Redelinghuys, senior trader at Inkunzi Investments.