(CNBC) — U.S. stocks closed mildly lower on Wednesday as investors remained anxious ahead of an impending Greek parliament vote.
"I honestly believe that's what got people a little on edge (Greek protests). Obviously there's been back and forth all day as to whether or not it will pass and Yellen did reiterate we were on pace for tightening and the impression that was given was September and here we are in July," said Michael O'Rourke of Jones Trading.
The Greek parliament faces a midnight deadline (5pm ET) to pass reforms needed to secure a bailout deal from its creditors. After defaulting on a loan to the International Monetary Fund at the beginning of July, Athens has another payment due to the European Central Bank Monday.
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