HONG KONG — President Trump fires off a tweet, and markets shudder.
Stocks around the world tumbled on Wednesday, a day after Mr. Trump posted a series of messages on Twitter warning that a fragile cease-fire in the trade war between the United States and China could be derailed. The declines in Asia and Europe came after stocks on Wall Street fell more than 3 percent on Tuesday.
But global investors appeared to be calmer than their counterparts in the United States, after official comments by the Chinese government that were vague but nevertheless expressed confidence that talks between the two countries would yield a positive outcome.
In Britain, France and Germany, stocks opened 1.3 percent to 1.5 percent lower. In Hong Kong and in Taipei, Taiwan, investors sent the market down 1.6 percent. Markets in Seoul, South Korea, and Tokyo finished about half a percent lower.
China’s currency, the renminbi, weakened slightly, by 0.3 percent, against the United States dollar on Wednesday. It trades within a band set by the People’s Bank of China. It had reached a two-month peak earlier this week.
Futures contracts that predict the performance of stocks in the United States indicated that shares there would rise when markets reopen on Thursday. They were to be closed on Wednesday in observance of the death of former President George Bush.
Conflicting signals on the trade front have sent investors on a wild ride this week. Just two days ago stocks rode a wave of optimism up after Mr. Trump and President Xi Jinping of China agreed a truce over dinner in Buenos Aires on the sidelines of the G20 meeting.
Since then, the White House has offered a mixed message about what, exactly, the two sides have agreed to. Mr. Trump has also chosen a trade hard-liner to lead the next round of talks. China’s Ministry of Commerce has said negotiations would follow a timeline. The two sides have 90 days to work out a resolution.
The biggest concern plaguing investors is that an extended trade war could erode global growth just as the world’s biggest economies are already starting to cool. In China, there are increasing worries that the dispute will weigh on an economy that is under stress from a plunging stock market, a weakening currency and dampened consumer appetite.
“While investing we try to avoid the noise, but these trade war issues in China and Japan have the potential of such large impact on certain industries it’s increasingly difficult to ignore,” said Seth Fischer, the chief investment officer at Oasis Management, a hedge fund based in Hong Kong. Mr. Fischer was referring to potential tariffs on the automobile industry that could affect the entire supply chain across Asia.
Mr. Trump referred to himself in one tweet on Tuesday as “a Tariff Man” In another, he wrote, “We are either going to have a REAL DEAL with China, or no deal at all — at which point we will be charging major Tariffs against Chinese product being shipped into the United States.”
Investors in the United States sent Treasury yields sharply down on Tuesday, a sign of broader concerns about growth. The difference between short- and long-term interest rates reached its lowest point since before the financial crisis, a signal that investors have warned precedes a recession.