At 1540 GMT, the rand was 1pc weaker at 14.4300 per dollar, its weakest level since May 9, after an overnight close of 14.2875.

With soft local economic data in the first half of the week and an escalation in the tariff spat between Washington and Beijing in the second half, the currency has struggled to hold on to gains it made following last week's general elections.

Tit-for-tat restrictions, including Beijing imposing higher tariffs on most US imports and US President Donald Trump blocking China's Huawei Technologies from buying vital American technology, have dented investor enthusiasm for risk assets.

And while the victory of South African President Cyril Ramaphosa's African National Congress (ANC) in parliamentary and provincial polls has been cheered by financial markets, investors are holding fire until he appoints a new cabinet.

"Market participants are acutely aware of the apparent fissures within the ANC, which may disrupt attempts at reform.

They may reserve judgement and are likely to look out for signposts to confirm the President's 'mandate'", economists at Sanlam Arthur Kamp said.

Bonds were also weaker, with the yield on the benchmark 10-year government issue adding 7 basis points to 8.495 pc.

On the bourse, stocks weakened on the back of US-China trade talks.

The broader All-Share index fell 0.63pc to 56,183 points, while the Top-40 index closed 0.55pc down at 50,081 points.

Among the losers was South African diversified industrial goods wholesaler Bidvest, down 4.32pc to 199.49 rand, while lender FirstRand fell 3.19pc to 65.80 rand.

US markets had a weak opening, suggesting volatility and posing a threat to South African markets, said Byron Lotter, Vestact Asset Management portfolio manager.

Local stocks such as investment house Rand Merchant Bank and Bidvest - often seen as proxies for local economic health along with other financial firms - fell.

Standard Bank slipped 3.1pc to 195.61 rand after ICBC Standard Bank announced the closure of its Tokyo metals branch.