ASX 200 set to open 23 points lower as US strikes on Iran lift WTI 3.38% and five heavyweights go ex-dividend

Sentiment: mixed ASX 200 futures: -0.25%

The S&P/ASX 200 is indicated 23 points or 0.25% lower at about 9,053 after US forces struck two Iranian rocket launchers on Larak Island inside the Strait of Hormuz, sending WTI crude up 3.38% to US$86.22 and Brent up 2.95% to US$90.70. Wall Street closed lower on the same escalation, the Dow Jones Industrial Average off 0.70% to 53,185.90 while the Nasdaq Composite limited its loss to 0.12% at 26,370.89. The US 10-year Treasury yield added 4 basis points to 4.76% as rate hike bets firmed, which left gold at US$4,449.61 an ounce even as the Iran strikes escalated.

Overnight drivers

• Crude oil: WTI +3.38% to US$86.22 and Brent +2.95% to US$90.70. US Central Command struck two Iranian rocket launchers on Larak Island after the IRGC was observed preparing to fire sea mines into the Strait of Hormuz, and Iranian state media reported retaliatory attacks on US bases in Jordan. WDS.AU, STO.AU, BPT.AU and KAR.AU closed Monday up between 0.25% and 0.58%, all of it before the move.
• US rates: the 10-year Treasury yield rose 4 basis points to 4.76%. Gold spot slipped 0.08% to US$4,449.61 and is down 4.36% over the week, so the escalation never reached bullion.
• Ex-dividend block: FMG.AU trades ex a 46 cent fully franked final today, worth 2.60% of Monday's $17.70 close. BEN.AU goes ex 33 cents (3.08% of $10.73), WOW.AU ex 52 cents (1.29% of $40.31), EDV.AU ex 1.2 cents, and WES.AU ex its FY26 final. Those resets subtract from the cash index arithmetically rather than through selling.
• Bulks and battery metals: coking coal +4.44% to US$282 a tonne and lithium carbonate +3.59% to CNY 158,500 a tonne. WHC.AU rose 2.52% on Monday and LTR.AU 2.51%.

Overnight Wall Street

• S&P 500: 7,686.14 (-0.33%)
• Nasdaq: 26,370.89 (-0.12%)
• Dow: 53,185.90 (-0.70%)
• Russell 2000: 2,956.45 (-0.54%)
• VIX: 14.92 (+3.40%)

The Dow Jones Industrial Average lost 374.09 points on 31 August 2026, twice the S&P 500's percentage decline, while the Nasdaq Composite gave up 0.12%. The VIX gained 3.40% to finish at 14.92. All three benchmarks still closed August higher, the S&P 500 up more than 2.5% for the month and the Dow about 1%, so one session of selling on the Iran strikes did not undo the month.

Commodities and FX (AU-relevant)

• Gold: US$4,449.61/oz (-0.08%)
• Brent: US$90.70 (+2.95%)
• WTI: US$86.22 (+3.38%)
• Iron ore 62% Qingdao: US$96.05/t (+0.22%)
• Copper: US$6.5981/lb (+0.55%)
• AUD/USD: 0.7168 (+0.05%)

Iron ore sat at US$96.05 a tonne, leaving BHP.AU, RIO.AU and FMG.AU without a fresh offshore signal after Monday falls of 1.59%, 1.81% and 2.05%. Platinum lost 3.05% to US$1,797.80 and palladium 4.56% to US$1,381.00, extending the selling in precious metals past gold. The Australian dollar bought 71.68 US cents, with the US dollar index 0.29% lower at 99.41.

Key themes for ASX open

• WDS.AU finished Monday at $32.42, STO.AU at $8.14, BPT.AU at $0.865 and KAR.AU at $1.750, every one of them marked before crude added better than 3%.
• Spot bullion barely moved overnight, so the gold miners open without a second catalyst after NST.AU fell 5.41%, EVN.AU 5.04%, CMM.AU 4.35% and GMD.AU 4.08% on Monday.
• Banks closed Monday firmly, CBA.AU +1.69%, WBC.AU +1.92%, ANZ.AU +1.28% and NAB.AU +0.89%, with the Australian 10-year bond yield at 5.108% after a 3 basis point rise.
• Lithium carbonate rose 3.59% overnight. LTR.AU closed Monday +2.51%, IGO.AU +1.28%, PLS.AU +0.75% and MIN.AU -1.27%.

Economic calendar today

• 11:30 AEST: Building Approvals, July (ABS)
• 11:30 AEST: Balance of Payments and International Investment Position, June quarter (ABS)
• 11:30 AEST: Government Finance Statistics, June quarter (ABS)

The balance of payments and government finance releases are both inputs to the June quarter national accounts, which land at 11:30 AEST on Wednesday.

What to watch

• Five ASX 200 members reset lower on dividends at 10:00 AEST, so the opening print will show a larger fall than the selling alone justifies.
• The ASX 200 closed Monday at 9,076.0, which is 195.6 points or 2.11% below its record close of 9,271.6 set on 6 August 2026.
• Australian June quarter GDP lands 11:30 AEST Wednesday.

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