All three major indices finished firmly in the red, with the S&P 500 losing 1.6 percent to 4,982.77 points, its first close below 5,000 points in nearly a year.

The Dow Jones industrial average ended down 0.8% to 37,645.59 points, about 1,780 points below the session high, and the technology-rich Nasdaq Composite index lost 2.2% to 15,267.91 points.

After three days of losses, Wall Street stocks opened briskly as traders took the White House's talks with Japan and South Korea in stride on hopes that Trump's trade assault could be short-lived.

As the day progressed, however, investors grew edgy as no concrete progress was made. Meanwhile, the White House confirmed plans for massive tariffs on China that will go into effect overnight.

"It's obvious that investors are clamoring for clarity, and there's none yet," said Jack Ablin of Cresset Capital, who estimated the market now sees more than a 50 percent chance of a U.S. recession.

Stocks have been in freefall since Trump's "Emancipation Day" event, at which he announced tariffs on major U.S. trading partners last Wednesday.

White House officials signaled openness to deal-making while criticizing China for introducing steep retaliatory tariffs in response to the new U.S. levies.

Trump plans to impose another 50 percent duty on Chinese goods at midnight on 9 p.m. (local time), bringing the additional rate on Chinese products to 104 percent.

All 11 sectors in the S&P 500 ended the day in the red, and most of the Dow was also in negative territory.

Among particularly big losers in the blue-chip index were Apple, down 5%, and Nike, down 4.2%.

But UnitedHealth Group rose 5.4 percent after the Trump administration finalized a rule to increase payments to insurers under the government's Medicare program. | BGNES