Major U.S. stock-indexes was boosted by gains in Apple and energy stocks on Wednesday, ahead of the Federal Reserve's policy statement later in the day.

Apple (AAPL) sold 48 million iPhones in the latest reported quarter and reported a near doubling of revenue from China, allaying concerns about its business in the world's second-largest economy.

While the central bank is not expected to raise rates at the meeting, traders will parse the statement for clues on when it will pull the trigger.

Most of Dow stocks in positive area (20 of 30). Top looser - The Boeing Company (BA, -1.32%). Top gainer - Apple Inc. (AAPL, +2.81%).

Most of S&P index sectors in positive area. Top looser - Basic Materials (+2,3%). Top looser - Utilities (-0.3%).

At the moment:

Dow 17592.00 +79.00 +0.45%

S&P 500 2072.75 +12.25 +0.59%

Nasdaq 100 4643.75 +11.50 +0.25%

Oil 45.86 +2.66 +6.16%

Gold 1176.90 +11.10 +0.95%

U.S. 10yr 2.07 +0.04