Stocks tumble ahead of Trump's China press conference

May 29 (UPI) -- President Donald Trump's upcoming news conference on China Friday shook up stocks in morning trading on Wall Street, as the White House could respond to the communist country's action against Hong Kong.

The Dow Jones Industrial Average fell more than 135 points in the first hour of Friday morning trading for a 0.40 percent drop. The S&P 500 was off 0.45 percent after the opening bell, losing more than 13 points. The Nasdaq Composite also slipped 0.25 percent after tumbling more than 20 points.

The Trump administration has suggested it would punish China for reining in Hong Kong's autonomy against its "One Country, Two Systems" approach it has operated under since 1997 when British rule ended.

Large pro-democracy demonstrations, which turned violent at times, last year after China tried to impose a change in extradition policy between Hong Kong and the mainland, made Beijing nervous and accused the United States and others of encouraging the controversy.

Secretary of State Mike Pompeo said Wednesday he notified Congress that Hong Kong is essentially no longer autonomous from mainland China after the communist country proposed a far-reaching new security law targeting pro-democracy protesters and foreign influences in the city.

Until Friday, stocks had been responding positively as states around the country announced staged re-openings of their economies. The Dow, for example, had gained more than 1,000 in the first two days of trading this week.