* US stocks open lower on jobs, non-manufacturing data
* Copper falls to 7-week low on concerns about China
* Euro at 17-month high against dollar, up 0.6 pct (Updates with U.S. markets open)
By Walter Brandimarte
NEW YORK, May 4 (Reuters) - Commodity prices fell on Wednesday, driving world stocks lower, as disappointing U.S. economic data and concerns about the slowdown of the Chinese economy prompted investors to scale back risky positions.
U.S. stocks and the dollar were further pressured by a report showing private employers added fewer jobs than expected in April and by a surprise slowdown of the U.S. services sector last month.
The dollar hit a session low against the euro as investors interpreted the data as the latest sign that the Federal Reserve will not withdraw economic stimulus any time soon, while European policymakers keep raising interest rates.
"This appears to be a bump in the road for the recovery if indeed the pace of job recovery has slowed," said Michael Woolfolk, strategist at BNY Mellon. "It certainly feeds into the notion that the Fed won't be hiking interest rates soon."
The U.S. Dollar Index <.DXY>, which measures the greenback against a basket of key currencies, fell more than 0.5 percent to a three-year low after the U.S. data.
The euro last traded at $1.4920
Concerns about the global economic recovery were on the rise as investors worried about further tightening measures in China, the world's top consumer of commodities.
Copper prices dropped to a seven-week low, with three-month contracts on the London Metal Exchange hitting a session low of $9,135 per tonne, the lowest since March 15, compared with $9,350 at the close on Tuesday.
"General risk appetite is under pressure at the moment. There are some fears over China -- will they tighten too much?" said Arne Lohmann Rasmussen, an analyst with Danske bank.
On Wall Street, disappointment with the economic data outweighed encouraging news of mergers and acquisitions.
The Dow Jones industrial average <.DJI> was down 117.61 points, or 0.92 percent, at 12,689.90. The Standard & Poor's 500 Index <.SPX> was down 12.57 points, or 0.93 percent, at 1,344.05. The Nasdaq Composite Index <.IXIC> was down 21.91 points, or 0.77 percent, at 2,819.71.
The MSCI All-Country World index <.MIWD00000PUS> lost 0.8 percent, after hitting its highest level in almost three years last week.
In Europe, the FTSEurofirst 300 index <.FTEU3> fell 1.4 percent, led by weak mining and oil shares. Emerging stocks <.MSCIEF> lost more than 1 percent.
Before this week's decline, world stocks had risen more than 8 percent this year as investors grew confident strong corporate earnings, robust growth in emerging markets and ample liquidity would keep global growth at a reasonable level.
U.S. crude oil
Portuguese bond yields fell after the country agreed to a three-year 78-billion-euro ($116 billion) bailout with the European Union and IMF on Tuesday, becoming the third euro zone country in a year, after Ireland and Greece, to seek financial aid. [ID:nLDE7420RT] (Additional reporting by Wanfeng Zhou, Ryan Vlastelica in New York and Melanie Burton in London; Editing by Dan Grebler)