Major U.S. stock-indexes fell on Tuesday as investors kept to the sidelines ahead of the Federal Reserve's policy meeting and a referendum on Britain's European Union membership. The Federal Open Market Committee (FOMC) will commence its two-day meeting on Tuesday to decide whether the U.S. economy has recovered enough to be able to absorb an interest rate hike. While traders have discounted a hike this month, they will parse Fed Chair Janet Yellen's speech at a conference on Wednesday for clues on the health of the economy and the trajectory of hikes.

Most all of Dow stocks in negative area (22 of 30). Top looser - American Express Company (AXP, -2,79%). Top looser - General Electric Company (GE, +0,62%).

All S&P sectors in negative area. Top looser - Conglomerates (-1,2%).

At the moment:

Dow 17546.00 -93.00 -0.53%

S&P 500 2059.25 -10.50 -0.51%

Nasdaq 100 4398.25 -20.50 -0.46%

Oil 48.25 -0.63 -1.29%

Gold 1288.30 +1.40 +0.11%

U.S. 10yr 1.60 -0.01