Wall Street sold off sharply on Friday after President Donald Trump revived a threat of new tariffs against China in response to the COVID-19 pandemic, which has brought global economies to a grinding halt.

All three major U.S. stock averages closed down well over 2%, and for the week they all lost ground.

May is often marked by sell-offs, and on the month's first day, with jitters on the rise as some U.S. states begin easing coronavirus shutdowns, the adage held true.

"Markets had a very strong April as they looked through the valley of economic weakness to a point when stimulus will reignite economic growth," said David Carter, chief investment officer at Lenox Wealth Advisors in New York. "But it could be a longer and deeper valley than many hoped."

Indeed, stocks had a remarkable run in April, with the S&P 500 and the Dow both posting their strongest monthly percentage gains in 33 years.

Trump said his administration was crafting retaliatory measures against China as punishment for the coronavirus outbreak, once again sparking tariff fears that rattled markets through much of the last two years. Trump has blamed China for what he says is "misinformation" when the virus emerged from the Chinese city of Wuhan and then quickly spread around the world.

"Trump poking China was the last thing markets needed given so much present economic and financial uncertainty," Carter added.

A mixed bag of earnings, particularly a disappointing report from Amazon.com, along with a fresh round of dismal economic data, also weighed on sentiment.

U.S. manufacturing activity skidded to an 11-year low last month as lockdowns shuttered factories, according to the Institute for Supply Management's purchasing managers index.

The Dow Jones Industrial Average fell 622.03 points, or 2.55%, to 23,723.69, the S&P 500 lost 81.72 points, or 2.81%, to 2,830.71, and the Nasdaq Composite dropped 284.60 points, or 3.2%, to 8,604.95.

All 11 sectors of the S&P 500 closed in the red, with energy companies suffering the largest percentage drop.

The corporate reporting season has crossed the midpoint, with 275 of the companies in the S&P 500 having reported quarterly results. Of those, 68% have beaten consensus estimates.

In aggregate, first-quarter S&P 500 earnings are seen having fallen 12.7% from a year ago, a stark reversal from the 6.3% annual growth forecast that stood on Jan. 1.

Tesla Inc plunged 10.3% after company Chief Executive Elon Musk said in a tweet that the electric car maker's stock price was "too high."

Amazon.com shares slid 7.6% after the online retailer warned pandemic-related expenses could lead to its first quarterly loss in five years.

Apple Inc's quarterly results beat expectations, but the iPhone maker declined to provide current-quarter forecasts. Its shares lost 1.6%.

Exxon Mobil dropped 7.2% after the company reported a drop in profit due to a massive $3 billion writedown on plummeting oil demand and prices.

Rival Chevron Corp posted a 38% profit increase, boosted by asset sales, and slashed spending plans. Its shares dipped 2.8%.

Declining issues outnumbered advancing ones on the NYSE by a 5.23-to-1 ratio; on Nasdaq, a 4.40-to-1 ratio favored decliners.

The S&P 500 posted no new 52-week highs and two new lows; the Nasdaq Composite recorded 17 new highs and 12 new lows.

Volume on U.S. exchanges was 10.17 billion shares, compared with the 12.19 billion average over the last 20 trading days. 

GLOBAL STOCKS

A sharp fall on Wall Street dragged a global stocks index down on Friday on concerns that the world's two largest economies could resume a trade war, with many financial markets closed for a holiday.

The euro rose and the U.S. dollar fell against most of its peers, and the pound succumbed to weak economic data. Crude oil prices traded in and out of negative territory.

London, Tokyo and New York markets were open on Friday, and stocks were pressured lower on tariff fears.

The benchmark London stocks index lost 2.34% and MSCI's gauge of stocks across the globe shed 2.21%. Japan's Nikkei lost 2.84%.

U.S. Treasury yields were little changed after data showed manufacturing activity in the world's largest economy plunged to an 11-year low in April.

Benchmark 10-year notes last fell 5/32 in price to yield 0.6386%, from 0.625% late on Thursday.

In a sign of the challenge facing global policymakers, the European Central Bank said on Friday the euro zone economy is likely to rebound in the second half of this year but may fail to return to last year's level until as late as 2022 due to the pandemic.

However, the euro rose the most in nearly six weeks.

The dollar index fell 0.068%, with the euro up 0.22% to $1.0979.

The Japanese yen strengthened 0.35% versus the greenback at 106.83 per dollar, while sterling was last trading at $1.2492, down 0.79% on the day.

The offshore Chinese yuan hit its weakest in a month versus the U.S. dollar after Trump's tariff threats.

Oil prices wobbled again as weak demand due to the virus and excess supply outweighed a record output cut by OPEC and its allies.

U.S. crude recently rose 6.9% to $20.14 per barrel and Brent was at $26.77, up 1.1% on the day.

Spot gold added 1.2% to $1,699.33 an ounce.