South Africa's rand slumped to its weakest in 18 months on Monday, while local stocks plunged before staging a recovery as US President Donald Trump's sweeping tariffs and global recession fears rocked financial markets.

At 1025 GMT, the rand traded at 19.31 against the dollar, down 1% from Friday's close, after earlier touching its weakest since October 2023.

Trump showed no sign of backing away from his tariff plans on Sunday, and investors worldwide poured into safe-haven currencies like the yen and Swiss franc on Monday. An emerging market stock index was heading for its biggest one-day selloff since the 2008 global financial crisis.

Local politics also weighed on the risk-sensitive rand, which lost more than 3% against the dollar last week.

The two biggest parties in South Africa's government have clashed over the national budget, and investors are worried the pro-business Democratic Alliance could quit or be forced out of the coalition with the bigger African National Congress.

"Any removal of the DA from the (coalition) would have a significantly negative effect on South Africa's outlook. It is the partnership between the ANC and DA that created a sense of stability and progress," said Casey Sprake, economist at Anchor Capital.

On the Johannesburg Stock Exchange, the Top-40 index slumped 5% in early trade to strike a nine-and-a-half-month low, before paring losses to trade down 0.3%.

Beermaker Anheuser-Busch was down 4.2%, Cartier owner Richemont down 3.2%, Anglo American down 1.6% and technology investor Naspers down 3.5%, among the decliners.

"The market is concerned that tariffs may cause an economic contraction and that they may be disruptive to the global supply chain," said Roy Topol, portfolio manager at Cratos Asset Management.

Naspers' fall was partly linked to weaknesses in China, where its European subsidiary Prosus holds a 24.1% stake in Tencent, analysts said.

South Africa's benchmark 2030 government bond rose slightly, as the yield fell 2 basis points to 9.39%.