Australian shares plunged 2% in a sea of red on Thursday as investors recoiled after US President Donald Trump announced sweeping tariffs on all imports, in a move that ratchets up a global trade war.

The S&P/ASX 200 index fell as much as 2.1% to 7,768 points by 0002 GMT. The benchmark recorded its biggest intraday loss since December 19, 2024.

Trump said on Wednesday he would impose a 10% baseline tariff on all imports and higher reciprocal duties on dozens of other countries.

"Stocks are diving following Trump unveiling tariffs that will hurt most global companies, Australian farmers, and investors alike", said Jessica Amir, a market analyst at trading platform Moomoo.

Heavyweight bank stocks dropped 2.3%, with Commonwealth Bank of Australia and National Australia Bank falling 1.6% and 2.5%, respectively.

Australia's no. 4 lender ANZ Group fell 3.2% after the bank regulator lashed it for what it called a failure to address wide-ranging problems.

Miners fell 1.7% as the tariff anxiety also hit commodities, including copper and aluminium, according to Amir.

Global miners BHP and Rio Tinto shed 2.3% and 2.4%, respectively.

Energy stocks lost as much as 3.2% to hit their lowest level since December 2021 as oil prices fell in post-settlement trade.

The healthcare sector, which is particularly exposed to tariffs on US exports, lost as much as 2.2%.

Fisher & Paykel Healthcare fell up to 3.1% after flagging a hit to earnings because of the tariffs, while hearing implant maker Cochlear was down 4.3%, even as it said it was awaiting more information on the levies.

Beef exporters Elders and Australian Agricultural Company shed as much as 2.7% and 3.9% respectively, as Trump indicated a ban on Australian beef — the country's largest export to the US

Information technology firms slipped 2.7%, tracking US futures, while gold stocks were up 0.9% as safe-haven demand pushed bullion prices higher.

New Zealand's benchmark S&P/NZX 50 index fell 1.3% to 12 161.45 points.