The Australian share market has followed US markets lower amid uncertainty sparked by US President Donald Trump's sacking of Secretary of State Rex Tillerson and fears that the US may move to impose tariffs on some goods from China.
The benchmark S&P/ASX200 index was down 49.9 points, or 0.84 per cent, at 5,924.8 points after the first half-hour of trade on Wednesday, with all sectors in the red.
In the US on Tuesday, the benchmark Dow Jones Industrial Average fell almost 0.7 per cent, after the market mood turned sour following the dismissal of Mr Tillerson.
President Trump fired Mr Tillerson after a series of public rifts over issues including North Korea and Russia.
Markets were also spooked by reports that the Office of the US Trade Representative has proposed tariffs on some Chinese products in retaliation for alleged intellectual property theft, which has sparked fears of a trade war.
Phillip Capital senior client adviser Michael Heffernan said events in the US were impacting the Australian market on Wednesday.
"Over the last couple of months, it's been an avalanche of left-fielders, Mr Heffernan said.
"Someone's lobbying a grenade over the parapet, with Tillerson getting the bullet, tariffs, Trump saying he will will speak with (North Korea's) Kim Jong-un."
On the local bourse, the big four banks were between 0.7 per cent and 1.2 per cent lower, with National Australia Bank at the rear.
The big miners were mixed: BHP Billiton was down 0.3 per cent at $28.595, Rio Tinto was up 0.4 per cent at $74.295, South 32 was 0.2 per cent lower at $3.175, and Fortescue Metals added 0.4 per cent to $4.69.
Oil and gas producer Woodside Petroleum was down 0.4 per cent at $28.74, and Santos fell 0.9 per cent to $4.885 in the wake of lower oil prices overnight.
News Corp was 30 cents, or 1.4 per cent, lower at $21.15.
NewsCorp is offloading a football highlights mobile app in a deal that will give it a stake in a video service co-owned by nine of the world's top clubs.
In economic news on Wednesday, the Australian Bureau of Statistics releases lending finance figures for January, and Reserve Bank Assistant Governor (Financial Markets) Christopher Kent speaks at the KangaNews DCM Summit, in Sydney.
The Australian dollar followed US stocks lower on the back of the Tillerson sacking, after earlier rising on the back of subdued US inflation figures.
At 1030 AEDT on Wednesday the Aussie was worth 78.57 US cents, down from 78.72 US cents on Tuesday.
ON THE ASX AT 1030 AEDT:
* The benchmark S&P/ASX200 was down 49.9 points, or 0.84 per cent, at 5,924.8 points
* The broader All Ordinaries index was down 48 points, or 0.79 per cent, at 6,029.1 points
* The SPI200 futures contract was down 45 points, or 0.75 per cent, at 5,923 points
* National turnover was 578.4 million securities traded worth $618.9 million