The Dow Jones industrial average rose 55 points, or 0.3 per cent, to 17,442 as of 12:02 p.m. Eastern time Wednesday. The Standard & Poor's 500 rose two points, or 0.1 per cent, to 2,031. The Nasdaq gained 17 points, or 0.4 per cent, to 4,699.
The Fed statement, due later Wednesday, is widely expected to repeat the pledge that the central bank will be "patient" in raising interest rates. Low rates are a key driver of the nearly six-year bull market for stocks.
Apple jumped 7 per cent after reporting record iPhone sales and earnings in its latest quarter. Boeing rose 6 per cent after commercial-jet demand boosted its latest quarterly profit.