Stocks in Europe and Asia soared on Thursday as relief flooded through financial markets after President Trump’s decision to pause punishing tariffs on dozens of countries..

Benchmark indexes rose more than 9 percent in Taiwan and Japan and 6 percent in South Korea. All three Asian economies were among the U.S. trading partners given a 90-day reprieve from Mr. Trump’s so-called reciprocal tariffs.

The Stoxx Europe 600 index jumped more than 5 percent as the higher tariffs were also lifted on the European Union. Benchmark indexes in Germany and France each gained more than 5 percent.

While those countries won’t immediately face the additional tariffs the Trump Administration had previously threatened, they will still be subject to a lower rate of 10 percent. Sector-specific tariffs, including a 25 percent levy on cars — a particular sore point for big auto exporters like Japan, South Korea and Germany — are still in place. Mr. Trump also did not walk back tariffs on China, which now exceed 100 percent.

In the United States, the reversal by Mr. Trump on Wednesday sparked the biggest one-day rally of the S&P 500 since October 2008, when stocks soared as investors anticipated central bank rate cuts in the wake of the global financial crisis.

But on Thursday morning, trading in the futures market pointed to a 2 percent decline in the S&P 500 index.

Analysts warned that tariffs remain higher than they were before Mr. Trump took office and that trade policy was unpredictable.

“Despite the good news, policy uncertainty remains elevated, and will act as a drag on the U.S. economy,” James Rossiter, the head of global macro strategy at TD Securities wrote in a note. “Firms will struggle to plan.”

Washington and Beijing have traded multiple rounds of tariffs, pushing the cost of their trade with one another to extraordinary levels. China leveled the latest salvo on Wednesday, bringing its across-the-board levies on American imports to 84 percent.

President Trump said on Wednesday that he did not think he would need to raise tariffs on China higher than 125 percent and that he expected Xi Jinping, China’s leader, to reach out about a deal. “I can’t imagine it. I don’t think we’ll have to do it more,” he said of additional tariffs on China. “No, I don’t see that.”

In trading on Thursday, stocks listed in Hong Kong gained around 2 percent, while those listed in Shanghai gained about 1 percent.

Takahide Kiuchi, executive economist at Nomura Research Institute in Tokyo, said that Mr. Trump’s latest moves show a shift in focus from reducing America’s trade deficits to gearing up for a trade war with China.

That means “risks have not been all that significantly reduced” for many countries like Japan and South Korea, which count China and the United States as their top trade partners, Mr. Kiuchi said.

The Chinese government has taken steps to stabilize its markets. State-owned companies on Tuesday announced they were buying back some shares, a move that typically helps push stock prices higher. On Thursday, an influential state media outlet published a commentary saying it was a good time for the central bank to lower interest rates and take other steps that would support the economy.

Over the past week, Mr. Trump’s trade broadsides have sent markets into a tailspin and threatened to upend global trade. Even after the rally on Wednesday, the S&P 500 remains roughly 12 percent below its February peak. It was also the index’s worst start to a presidential term since the dot-com bubble burst at the start of 2001.

In Asia, stock benchmarks have dropped around 12 percent in Japan, and more than 16 percent in Taiwan this year. South Korea’s Kospi index has remained roughly flat.

Ryan Young, a senior economist with the Competitive Enterprise Institute, said Mr. Trump’s pivot on tariffs was a relief. But he remains concerned that uncertainty about future policies will continue to paralyze long-term investment. The administration’s tariff actions “have already done a lot of damage, and this pause does not undo it,” Mr. Young said. “Markets want stability.”

Berry Wang contributed research from Hong Kong.