The S&P/ASX200 gained 49.2 points by midday on Wednesday, to be up 0.55 per cent to 8,966.9, as the broader All Ordinaries improved by 52.7 points, or 0.58 per cent, to 9,184.
Energy and utilities stocks weighed heavily, each sector down more than two per cent in early trade as Brent oil futures fell below $US80 a barrel, the lowest price since the beginning of March and shortly after US-led air strikes on Iran sparked the biggest energy supply shock in history.
Ampol and Viva Energy both sold off, but the refinery operators' share prices are still up roughly 20 per cent on their pre-conflict prices.
The materials sector swung in the other direction on the prospect of easing fuel costs and as gold miners continued to rebound from recent weakness.
Gold is trading at $US4,343 ($A6,144) an ounce, after tumbling for weeks on fears higher global inflation would force more central banks to hike interest rates, weighing on non-yielding assets.
"Australian investors are taking some comfort in lower oil prices, easing geopolitical tensions and a steady rate environment," Moomoo dealing manager Chris Strazzeri.
"It's all broadly supportive of sentiment, but investors are still showing signs of caution when it comes to local high-growth sectors.
"All investors will focus on the US rate decision tomorrow, which are expected to stay on hold, but commentary from the new chairman (Kevin Warsh) will be critical."
BHP edged 0.4 per cent higher to a new intraday high of $65.78 as copper prices firmed, while iron ore futures have struggled to snap out of their recent funk to trade around $US101.40 a tonne amid persistent oversupply concerns.
The heavyweight financials sector edged 0.5 per cent higher, putting it on track for a fourth straight session of gains as Commonwealth Bank led the big four banks into the green, while investment giant Macquarie hit a fresh record, trading above $250 per share for the first time.
ARN Media shares soared by more than a quarter after the media company settled its legal stoush with shock jock Karl Sandilands for $12.1 million, following the termination of his $100 million, 10-year Kyle and Jackie O Show contract.
Flight Centre shares jumped more than four per cent, despite the company cutting its 2026 guidance, forecasting a maximum underlying profit of $295 million, down from a previously flagged $345 million.
Qantas and Virgin Australia continued to rebound from recent selling pressure on the prospect of cooling jet fuel prices and easing air travel disturbances.
The Australian dollar was buying 70.68 US cents, up from 70.55 US cents on Tuesday at 5pm.
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