“Trade in 2020 will fall steeply in every region of the world and basically across all sectors,” Roberto Azevêdo, director general of the W.T.O., said in a video briefing.

The W.T.O. economists believe the sharp fall will be worse than the trade slump from the 2008 financial crisis. Global trade could rebound rapidly, but it would depend on how quickly the pandemic was brought under control, and the policy choices governments took to support their economies, Mr. Azevêdo said.

Germany and France, Europe’s largest economies, warned that they were headed toward their sharpest downturns since World War II, even as some European countries moved toward a loosening of restrictions put in place to slow the spread of the virus.

More than 1.4 million cases of the virus have been confirmed across at least 177 countries, and 86,000 people have died. Here are the latest updates from the U.S., where the virus has stricken more than 418,000 people. We also have the international picture and maps of the pandemic.

Stocks in the U.S. climbed as investors weighed data showing the extent of the economic damage wrought by the coronavirus pandemic against signs of progress in the effort to contain it. The S&P 500 rose more than 2 percent while major indexes in Europe were slightly lower.

New York State, the epicenter of the U.S. outbreak, has now confirmed more than 149,000 cases — a higher number than any country outside the United States, including Italy and Spain, the two other countries the pandemic has hit hardest. The death toll hit another daily high but the rate of hospitalizations was flattening.

As many as 150 Saudi royals are believed to have contracted the coronavirus. King Salman, 84, has secluded himself in an island palace on the Red Sea, while Crown Prince Mohammed bin Salman has retreated with many of his ministers to a remote site on the same coast.

The Chinese Communist Party is investigating an outspoken property tycoon, Ren Zhiqiang, who accused President Xi Jinping of having mishandled the coronavirus outbreak. Mr. Ren, a longtime party member, disappeared last month after having written an essay describing Mr. Xi as a power-hungry “clown.

After a second night in intensive care, Prime Minister Boris Johnson was stable and “responding to treatment” for the coronavirus, a spokesman said. Britain reported 938 new coronavirus deaths on Wednesday, its highest single-day figure.

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