Markets: Oil shock and rising yields keep investors on edge

South African markets were being pulled lower on Tuesday by a combination of higher oil prices, a weaker rand and rising global bond yields. Continued uncertainty over the conflict in the Middle East was reshaping expectations for inflation and interest rates, while international markets faced similar pressures as investors reassessed the prospect of rates remaining higher for longer.

The rand extended its recent losses, trading at about R16.42 to the US dollar. Higher oil prices and a firmer dollar were weighing on the currency, while investors were also watching forthcoming US economic data for clues to the Federal Reserve’s next move.

The pressure followed a difficult session on the JSE. The Top 40 index fell 1.7% in early trading on Monday, while the yield on the benchmark 2035 government bond rose by 5.5 basis points to 8.855%. Gold Fields was among the biggest casualties, falling by about 13% after Australia’s Northern Star Resources rejected the miner’s unsolicited A$38.7 billion takeover proposal.

Oil remains a particular concern for South Africa, given its reliance on imported fuel. Brent crude rose for a second consecutive session on Tuesday to $105.91 a barrel, while US West Texas Intermediate stood at $93.32, amid continued concern about potential disruption to Middle Eastern supplies linked to the US-Iran conflict.

There was more encouraging news on investment flows. South Africa’s foreign direct investment inflows rose to R49.8 billion in the second quarter of 2026, from R20.3 billion in the first quarter, according to the South African Reserve Bank. The increase was largely attributable to debt funding received by a local telecommunications company from its non-resident parent.

Portfolio investment told a different story. Non-residents recorded a R9 billion portfolio outflow in the second quarter, compared with a R9 billion inflow in the previous quarter, as foreign investors sold R34.2 billion in South African equities while buying R25.1 billion in domestic debt securities, Sunday World reported.

For the domestic economy, the combination of a weaker rand and expensive crude matters because sustained increases in fuel and transport costs risk feeding into inflation and complicating the interest-rate outlook.

Internationally, the dominant themes were the continued rise in oil prices and government bond yields. US 10-year Treasury yields hovered around 5.27%, close to a 19-year high, while French 10-year yields stood at their highest level since 2008. The moves reflected a broader reassessment of the global interest-rate outlook.

Higher sovereign yields matter beyond government finances because they set the benchmark against which household and business borrowing costs are priced.

US equities suffered another weak session on Monday, with the Dow Jones Industrial Average falling by 0.67%, the S&P 500 by 0.77% and the Nasdaq by 0.92%. Rising oil prices and Treasury yields weighed on sentiment, alongside uncertainty over the prospects for a US-Iran peace agreement, Reuters reported.

The dollar strengthened on Tuesday as Treasury yields rose and investors considered the possibility that higher energy prices could keep inflation elevated. The euro fell by 0.24% to $1.1344, while sterling declined by 0.2% to $1.3228, Reuters reported. A stronger dollar tends to draw capital towards dollar-denominated assets, adding further pressure to emerging-market currencies.

Asian markets were also under strain. Indian equities extended their losses, with the Nifty 50 falling by 0.28% and the BSE Sensex by 0.33%, as the absence of a Middle East peace deal pushed up oil prices and bond yields and raised concerns about foreign investor outflows from India, Reuters reported.

Indonesia’s rupiah fell through 18,000 to the dollar, reaching its weakest level since early August. Reuters attributed the move to higher US Treasury yields, a stronger dollar, rising oil prices and continuing US-Iran tensions.

Oil remained the central commodity story, with Brent above $106 a barrel on Tuesday as markets continued to price in the possibility of prolonged disruption to Middle Eastern energy supplies, Reuters reported.

The resulting inflation concerns are feeding directly into interest-rate expectations. Two-year US Treasury yields have risen by almost 60 basis points during September, putting them on course for their biggest monthly increase since early 2023, Reuters reported.

The higher-yield environment has also left gold volatile as investors weigh geopolitical risk against the appeal of interest-bearing assets when bond yields are rising.

For South African investors and businesses, three developments stand out in the sessions ahead:

• Oil prices above $100 a barrel could translate into higher fuel and transport costs and renewed inflationary pressure.
• A stronger dollar and higher US yields continue to pressure emerging-market currencies, including the rand.
• Rising global yields are challenging expectations that major central banks will be able to ease policy quickly if inflation remains elevated.

Market direction is likely to remain closely tied to developments in the Middle East, crude-price movements and incoming US data. Investors will be watching this week’s PCE inflation index and non-farm payrolls figures for clues to the Federal Reserve’s next move.

*ADDITIONAL SOURCES: CNBC Africa & Market Screener.