The local share market has fallen amid fears the Middle East conflict could delay US interest rate cuts, even after President Donald Trump extended a ceasefire with Iran at the request of Pakistani mediators.
At noon AEST on Wednesday, the benchmark S&P/ASX200 index was down 80.8 points, or 0.9 per cent, to 8,868.6, while the broader All Ordinaries was down 80.6 points, or 0.88 per cent, to 9,096.5.
Mr Trump said in a social media post he was extending the two-week ceasefire, which had been set to expire at 10am AEST on Thursday, because the Iranian government was "seriously fractured" and hadn't submitted a unified proposal.
But negotiators in Tehran said they wouldn't attend talks with the US, calling them a waste of time, Iranian state media reported.
Also in Washington, Mr Trump's pick to chair the US Federal Reserve struck a hawkish stance during his Senate nomination hearing.
Kevin Warsh said Mr Trump had never asked him to commit to interest rate cuts and told the Senate Banking Committee that fighting inflation would be his top priority.
The market's implied odds for a US interest rate cut by December fell to just 27.9 per cent after the meeting, from 36.2 per cent a day earlier, according to CME Fedwatch.
At midday, six of the ASX's 11 sectors were lower and four were higher, with industrials basically flat.
Health care was by far the biggest mover, falling 5.4 per cent on a huge plunge by Cochlear.
The hearing implant company dropped 41.4 per cent to a decade-low of $98.36 after cutting guidance, in part due to uncertainty and reduced consumer sentiment from the Middle East conflict.
Cochlear said it now expects to make a full-year profit of just $290 million to $330 million, down from its original guidance of $435 million to $460 million.
Elsewhere, the big four banks were all lower.
CBA had dropped 2.5 per cent, ANZ and Westpac had both fallen 1.5 per cent and NAB had dipped 1.0 per cent.
Bank of Queensland had slid 9.0 per cent to a three-month low of $6.615 after the regional bank announced its first-half profit had fallen 20 per cent to $136 million.
In the heavyweight mining sector, BHP had grown 1.3 per cent to $56.21 after the Big Australian said its full-year copper production was now expected to be at the upper half of guidance range.
Fortescue was down 0.5 per cent, Rio Tinto was basically flat and South32 added 1.4 per cent.
Goldminers were lower as the yellow metal changed hands at $US4,771 an ounce, down from about $4,800 on Tuesday.
Evolution was down 3.7 per cent, Westgold had fallen 4.6 per cent and Northern Star had retreated 3.5 per cent.
The Australian dollar was trading for 71.60 US cents, from 71.63 US cents at 5pm on Tuesday.
