U.S. stock index futures indicated a flat open on Tuesday ahead of the two-day Federal Open Market Committee (FOMC) meeting, housing data and a busy day of earnings.
The Fed meeting gets underway Tuesday, with the conclusion and post-meeting statement due Wednesday. A wave of disappointing domestic data since the previous FOMC meeting has spurred economists to downgrade their outlooks for the U.S. economy in 2015. Investors will be eyeing any comments from the Fed for hints as to when it might hike interest rates.
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Standout data due Tuesday include April's Conference Board consumer confidence survey results at 10.00 a.m. ET. They are expected to register a rise, consistent with a positive spending impetus among households.
The S&P/Case-Shiller's 20-City Composite gained 5 percent year-over-year in February, compared with a 4.5 percent increase in January.
The data was expected to show continued moderate growth just shy of 5 percent year-on-year in the 20 largest U.S. metro areas.
Major earnings on Tuesday include Bristol-Myers Squibb, Ford, Honda Motor, Merck, Pfizer, UPS, Coach, T-Mobile US, JetBlue, Oshkosh ahead of market open.
Reports from Twitter, Samsung Electronics, Kraft Foods, GoPro, Buffalo Wild Wings are all due after the bell.
It comes after U.S. stocks closed lower on Monday, failing to hold Friday's records.
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Stocks to watch include Apple, which closed up 1.8 percent, recovering some early losses, ahead of its fiscal second-quarter report. The company reported second-quarter earnings of $2.33 per share on revenue of $58 billion on Monday. Analysts expected tech giant Apple to report earnings of $2.16 a share and $56.08 billion in revenue, according to a consensus estimate from Thomson Reuters.
BP shares edged higher in London trading after it managed to beat its own profit expectations in a first-quarter release before the opening bell
Pfizer's stock traded slightly lower ahead of the bell after lowering its 2015 guidance for earnings per share and revenue. The pharmaceutical giant also reported quarterly adjusted profits of 51 cent per share on revenue of $10.86 billion, both of which beat Wall Street estimates.
In Europe, equities were in negative territory in morning trade on Tuesday, as investors took a breather from a stellar rally in the previous session and looked ahead to the Fed meeting.
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Greek Prime Minister, Alexis Tsipras, said on Monday that he may resort to a referendum if lenders insist on demands that the government deems unacceptable, Reuters reported. But he added that he was confident of striking a deal to avoid such a scenario.
—CNBC's Fred Imbert contributed to this report