Asian equities mostly fell Wednesday as investors fret over President Donald Trump's ever-changing trade policies amid increasing concern that his tariffs could send the US economy into recession.

Global markets have endured severe volatility this month as the president looks to ramp up pressure on global partners by imposing or threatening hefty duties on their goods, citing huge trade imbalances.

In the latest move, sweeping 25 percent levies on all US aluminum and steel imports came into effect at midnight in Washington (0400 GMT Wednesday), hitting numerous nations from Brazil to South Korea, as well as the European Union.

On Tuesday, Trump threatened to double those on Canada after the province of Ontario imposed an electricity surcharge on three US states. The president called that off after Ontario halted the charge.

The on-off nature of the trade policies has fueled uncertainty in markets, and has sent the VIX "fear index" of volatility to its highest level since August.

Traders appeared largely unmoved by Trump's attempt to soothe worries over a recession after he warned at the weekend of "a period of transition" and refused to rule out a downturn.

On Tuesday, he said at the White House: "I don't see it at all. I think this country's going to boom, adding that markets "are going to go up and they're going to go down. But you know what, we have to rebuild our country".

But Nicole Inui at HSBC wrote in a note: "The back and forth on tariff announcements is playing havoc with consumer and business confidence: policy uncertainty is at a record high, consumer confidence dropped sharply and small business optimism has pared back.

"Consensus GDP forecasts were revised lower for the first time in eight months and market chatter about recession is creeping higher."

After another selloff in New York that saw the Nasdaq extend Monday's four percent dive, Asian traders were also in a dour mood.

Tokyo edged up with Singapore, Seoul, Jakarta and Taipei.

But Hong Kong, Shanghai, Wellington, Mumbai, Bangkok and Manila were in the red, with Sydney down more than one percent, on concerns about the impact of Trump's latest tariffs on Australia's economy.

Also in focus Wednesday is the release of key US consumer inflation data, which the Federal Reserve will keep a close eye on as it tries to determine monetary policy in light of the latest moves by Trump.

There is a fear that the tariffs, and plans to slash taxes, regulation and immigration will fan inflation again, forcing the bank to hold borrowing costs for longer or even hike them.

Meanwhile, analysts said high uncertainty in US markets at the moment was making other regions more attractive as investors look for more stability.

"For years, the US has been the undisputed leader of global markets, fueled by aggressive fiscal spending, tech dominance, and a strong consumer," said Charu Chanana, chief investment strategist at Saxo markets.

"But cracks are starting to show. Investors are increasingly looking overseas as concerns mount over US stock valuations, monetary policy, and economic uncertainty."

Key figures around 0700 GMT

Tokyo - Nikkei 225: UP 0.1 percent at 36,819.09 (close)

Hong Kong - Hang Seng Index: DOWN 1.1 percent at 23,520.71

Shanghai - Composite: DOWN 0.2 percent at 3,371.92 (close)

Euro/dollar: DOWN at $1.0900 from $1.0915 on Tuesday

Pound/dollar: DOWN at $1.2926 from $1.2954

Dollar/yen: UP at 148.20 yen from 147.70 yen

Euro/pound: UP at 84.32 pence from 84.26 pence

West Texas Intermediate: UP 0.1 percent at $66.34 per barrel

Brent North Sea Crude: UP 0.1 percent at $69.66 per barrel

New York - Dow: DOWN 1.1 percent at 41,433.48 points (close)

London - FTSE 100: DOWN 1.2 percent at 8,495.99 (close)