Wall Street opens lower after Trump's government shutdown threats

US stock indices opened lower on Wednesday after president Donald Trump threatened to shut the government if he didn't get the funds necessary to build the wall along the border with Mexico, while asserting the failure of the current trade talks with both Canada and Mexico and threatening to get rid of the NAFTA trade deal. 

Earlier US data showed the manufacturing PMI slowed down unexpectedly, while services PMI widened more than expected according to preliminary readings for August, as new home sales tumbled unexpectedly in July. 

Now markets await the Jackson Hole Symposium later this week.. the Economic Symposium, held in Jackson Hole, Wyoming, is attended by central bankers, finance ministers, academics, and financial market participants from around the world. The meetings are closed to the press but officials usually talk with reporters throughout the day.

Comments and speeches from central bankers and other influential officials can create significant market volatility, especially from major global figures such as Fed Chair Janet Yellen and governors of central banks in Japan, England, and Europe. 

As of 03:23 GMT, Standard and Poor's 500 shed 0.28%, or 6.92 points to 2,445.78, while Dow Jones declined 0.25%, or 62.29 points to 21,837.60. 

Tech-heavy NASDAQ dropped 0.29%, or 18.59 points to 6,278.75.