U.S. stocks waver amid Yellen's testimony

U.S. stocks fluctuated narrowly in the morning session Tuesday, as Wall Street digested Federal Reserve Chair Janet Yellen's comments delivered during her semi-annual testimony.

By midday, the Dow Jones Industrial Average rose 16.23 points, or 0.09 percent, to 17,821.10. The S&P 500 added 3.49 points, or 0.17 percent, to 2,086.74. The Nasdaq Composite Index fell 1.98 points, or 0.04 percent, to 4,835.24.

Yellen kicked off her two-day testimony before Congress with a session scheduled Tuesday morning before the Senate Banking Committee.

She reiterated the cautious approach to raising interest rates that the Federal Open Market Committee signaled last week after its policy meeting.

With a weak global economy, low U.S. productivity and other factors holding down interest rates in the long run, Yellen said the Fed's benchmark overnight interest rate is likely to remain low "for some time."

After the conclusion of a two-day meeting last week, the U.S. central bank decided to keep its federal fund rate unchanged.

According to the statement released after the meeting, the Fed continued to lean toward hiking rates. However, the Fed's "dot plot", shows that six members now believe there will be just one rate hike this year, up from one member in March.

Meanwhile, Britain's referendum was also in focus, which is set for Thursday. The latest polls showed the Remain camp making gains after the killing of British politician Jo Cox.

There is no major economic data due out Tuesday. Enditem