U.S. markets are slightly lower after hitting a 3.5-year closing high, as investors wait for news out of Greece. Earnings from Cisco and Groupon were on tap.

Europe markets closed mostly higher as Greek political leaders met in Athens. Investors await a European Central Bank meeting to see if Mario Draghi will tip his hand.

U.S. stock index futures pointed to a higher open for Wall Street on Wednesday, with investors positioning for a favorable resolution to the Greek sovereign debt crisis.