Renewed worries about possible U.S. military intervention in Syria sent global stock markets lower on Wednesday.

Analysts at Credit Agricole CIB in Hong Kong said the optimism brought about by better-than-expected U.S. manufacturing for August dissipated amid fears of a possible escalation in Syria’s civil war following a chemical attack that killed scores of civilians. The U.S. government contends the regime of Syrian President Bashar Assad is responsible.

Analyst Gary Yau said in a commentary that “we expect no major shift in sentiment today despite a number of data scheduled for releases, as investors are set to stay cautious with one eye on the Syria development,” ahead of this week’s G-20 gathering of world leaders in Russia and U.S. employment data on Friday.

Japan’s Nikkei 225 reversed early losses and rose 0.5 percent to close at 14,053.87, but benchmarks elsewhere in Asia fell. South Korea’s Kospi declined less than 0.1 percent to 1,933.03. Australia’s S&P/ASX 200 shed 0.7 percent to 5,161.60. Hong Kong’s Hang Seng lost 0.3 percent to 22,326.22.

In early trading in Europe, Britain’s FTSE 100 lost 0.5 percent to 6,434.37. Germany’s DAX declined 0.4 percent to 8,146.52 and France’s CAC-40 dropped 0.7 percent to 3,945.54.

Futures augured losses on Wall Street. Dow Jones industrial futures fell 0.1 percent to 14,811 and S&P 500 futures were 0.2 percent down at 1,636.80.

President Barack Obama has faced difficulty trying to amass support for U.S. military intervention in Syria, where an alleged chemical attack by government forces killed scores of civilians outside of Damascus. Britain’s parliament voted against involvement, and Russia, a strong ally of Syria, has been sharply critical.

However, Mr. Obama got a critical boost on Tuesday when a top U.S. lawmaker said he backed the U.S. president’s call for a military strike. That intensified worries about the possible expansion of a conflict in an already volatile region of the world.

Still, the investment mood was held somewhat intact by an increase in corporate deal-making and growing confidence in the global economy. Verizon agreed on Monday to buy out the remaining stake in its mobile phone business from Vodafone in a massive $130 billion deal and Microsoft announced Tuesday it would take over Nokia’s smartphone business and a portfolio of patents and services.

TV maker TCL Multimedia Technology Holdings rose nearly 10 percent in Hong Kong after announcing it was teaming up with Chinese Internet company Baidu to make a smart TV that will sell for 4,567 yuan ($746).

Big Chinese paper makers registered gains for a second day after the Chinese government indicated it was in favour of reforming the industry to reduce overcapacity. Nine Dragons Paper Holdings rose more than 7 percent.

“Investors are focusing on individual shares that have positive news on the corporate earnings side or maybe on industry policy,” said Kwong Man Bun, chief operating officer at KGI Securities in Hong Kong.

Benchmark crude for October delivery was down 36 cents to $108.18 a barrel in electronic trading on the New York Mercantile Exchange. The contract fell $1.15 to close at $107.65 on Friday.

In currencies, the euro rose to $1.3178 from $1.3169 late Tuesday. The dollar fell to 99.56 yen from 99.62 yen.

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