Wall Street jittery ahead of crucial Greek bailout talks

U.S. stock index futures signaled a mixed to slightly lower open on Wednesday, ahead of a crucial meeting of European finance ministers to discuss Greece's soon-to-end bailout program.

Greek Finance Minister Yanis Varoufakis is due to meet with other euro zone finance ministers at 11:30 a.m. ET Wednesday and is expected to unveil new reform proposals and an overhauled bailout plan.

Yanis Varoufakis Greece
Alkis Konstantinidis | Reuters

Varoufakis is also expected to ask for a "bridge program" to cover the government's funding needs while a new debt pact is agreed.

European equities traded lower ahead of the Eurogroup meeting of finance ministers.

Wednesday is also a heavy earnings day, with the likes of PepsiCo, Time Warner, AOL, animal healthcare firm Zoetis and Generac reporting ahead of market open.

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Numbers from Baidu, Tesla Motors, Cisco Systems, MetLife, NetApp, Whole Foods, Applied Materials, Equifax and TripAdvisor are all due after the bell.

On the data front it is set to be a quiet day, aside from the release of the monthly Federal Budget statement at 2:00 p.m. ET.