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* Twitter, Facebook in focus (Updates to close)

By Caroline Valetkevitch

May 28 (Reuters) - Wall Street ended lower on Thursday following a late-session reversal, with Facebook weighing on the market after President Donald Trump said he would sign an executive order related to social media companies and said he would hold a news conference on China on Friday.

Stocks had been higher for most of the session as investors continued to bet on a swift recovery from the coronavirus-driven economic slump.

Worsening ties between the United States and China in recent weeks and fears of a second wave of coronavirus infections pose a threat to the stock market's strong recovery from its steep selloff, according to analysts.

"There have been issues with comments from the White House on tech," said Quincy Krosby, chief market strategist at Prudential Financial in Newark, New Jersey.

But recent strong gains in the market have also caused some investors to pull back.

Unofficially, the Dow Jones Industrial Average fell 147.67 points, or 0.58%, to 25,400.6, the S&P 500 lost 6.41 points, or 0.21%, to 3,029.72, and the Nasdaq Composite dropped 43.37 points, or 0.46%, to 9,368.99.

(Reporting by Caroline Valetkevitch in New York; Editing by Leslie Adler)