One of the few major exchange-traded funds trading lower into midweek was the iShares Dow Jones Transportation Average Index Fund ETF (NYSE: IYT). IYT has traded lower for the past two days in a row after rallying to their highest levels since the summer of 2011.

Currency markets were holding steady in tight ranges in European trading as participants refrained from placing new bets without firm news of a political deal in Greece.

Germany's latest offer of five-year debt attracted solid demand at its latest auction as borrowing costs rose only slightly from recent record lows.

European stocks were modestly higher as investors hoped that Greek lawmakers were close to a deal on the restructuring of Greece's debt.

U.S. banks have been dogged in recent years by tougher regulation and sluggish loan growth. But Citigroup believes things will turn around for its U.S. retail-banking operations.