The currency fell 1.3 percent on Friday and was last at US$0.7107.
Europe's resistance to the gloom was led by Milan, which jumped 1.5 percent as soothing comments on Italy's upcoming budget by Economy Minister Giovanni Tria pushed down the country's borrowing costs in the bond markets.
The tariffs, ranging from 5% to 25%, would apply to 5,207 products, and U.S. actions will determine whether China adopts the additional duties, Beijing said at the time.
Singapore slipped 0.6 percent and Taipei shed 1.1 percent, while Bangkok and Jakarta were also sharply lower. It makes many of its products for the USA market in China, and it also sells gadgets including the iPhone in China, making them a potential target for Chinese retaliation against the Trump tariffs.
The crown rose about 0.6 percent against the euro to 10.43 crowns.
Japan's Nikkei, which had opened lower, ended 0.3 percent higher after revised second-quarter gross domestic product data showed the world's third-biggest economy grew at its fastest pace since 2016.
Trump, who is challenging China, Mexico, Canada and the European Union on trade issues, has also expressed displeasure about the large USA trade deficit with Japan.
Chinese shares weakened, with the blue-chip index off 0.6 percent while Shanghai's SSE Composite stumbled 0.4 percent.
"Markets had some hope that as we got to that deadline there would be some concessions, but there's really escalation", Sean Fenton, director at Tribeca Investment Partners, told Bloomberg Television.
The greenback has already rallied against a number of emerging markets units - with India's rupee at record lows and the Indonesian rupiah at a 20-year trough - on fears that economic crises in Argentina, South Africa and Turkey could spread globally.
Copper tumbled over 1.2 percent to cement the 20 percent drop it has seen already this year.
Spot gold was mostly unchanged at US$1,194.84.
Oil prices bucked the trend, after three straight days of losses. "That uncertainty could result in more stock market volatility as investors worry that the Fed may move too far in its normalization campaign".
In commodities, oil prices were firmer after three straight days of losses, with USA crude futures up 44 cents at US$68.19 per barrel.