At 1519 GMT, the rand traded at 19.2550 against the dollar, around 0.93% weaker than its previous close.

On Wednesday, the dollar reached a high of 103.120 against a basket of global currencies. It last traded at 102.950 as U.S. debt ceiling talks continue.

Locally, Statistics South Africa data showed a 1.6% drop in year-on-year retail sales in March. Analysts polled by Reuters predicted a 0.7% decline.

Sentiment also soured on local media reports of a further delay to maintenance at the country's only nuclear power station, heightening fears that an ongoing power crisis will deepen.

EE Business Intelligence reported that one of the Koeberg's plants reactors currently offline for maintenance will be shut for a further 200 days.

The country faces its worst blackouts on record, leaving households and businesses without power for up to 10 hours daily and crippling the economy. JP Morgan predicts a 0.2% contraction of gross domestic product for 2023.

Last week, the rand hit an all-time low of 19.5100 against the dollar following record power cuts and allegations that South Africa shipped weapons for Russia.

South Africa's Eurobonds fell up to 1.7 cents in the dollar, with the 2052 maturity down 1.669 cents to 80.119 cents at 1531 GMT, according to Tradeweb data.

"South Africa's Eurobonds are back on the defensive today," said Kieran Siney of ETM Analytics.

"The news (of the Koeberg shutdown) has come as a fresh headwind ... following the Russia saga and (the) worsening electricity crisis."

On the Johannesburg Stock Exchange the blue-chip Top-40 ended the day 0.74% higher and the broader all-share index closed 0.54% up.

The benchmark local 2030 government bond weakened, with the yield closing up 30 basis points at 11.055%.

(Reporting by Tannur Anders and Rachel Savage; Additional reporting by Carien du Plessis; Editing by Bhargav Acharya, Barbara Lewis, Sherry Jacob-Phillips and John Stonestreet)

By Tannur Anders and Rachel Savage