U.S. stocks ended higher on Wednesday, as the Federal Reserve announced start of balance sheet reduction from October.

The Dow Jones Industrial Average gained 41.79 points, or 0.19 percent, to 22,412.59. The S&P 500 added 1.59 points, or 0.06 percent, to 2,508.24. The Nasdaq Composite Index was down 5.28 points, or 0.08 percent, to 6,456.04.

The U.S. Federal Reserve on Wednesday kept interest rates unchanged, but announced that it will start to unwind its 4.5-trillion-U.S.-dollar balance sheet from October, a further step to end the loose monetary policy.

"Information received since the Federal Open Market Committee met in July indicates that the labor market has continued to strengthen and that economic activity has been rising moderately so far this year," said the Fed in a statement released after its two-day monetary policy meeting.

The central bank said Hurricanes Harvey, Irma and Maris were expected to affect U.S. economy in the near term, while they would not alter the course of the economy in the medium term.

Fed officials continue to expect that the U.S. economy will expand at a moderate pace in the future.

On the economic front, the National Association of Realtors said on Wednesday that existing home sales decreased 1.7 percent to a seasonally adjusted annual rate of 5.35 million units last month. That was the lowest level since August 2016.