Wall Street uneasy ahead of busy data week

U.S. stock index futures indicated a flat to slightly lower open on Monday, amid some dollar and oil price weakness, ahead of a busy week of data releases.

Greece debt talks also remained in focus as German Chancellor Angela Merkel and Greek Prime Minister Alexis Tsipras were set to meet in Berlin.

After a strong close on Friday which saw stocks surge about 1 percent, the scheduled release of top-tier data Monday put investors on edge again, while gains clocked up by crude on Friday were pared after comments from Saudi Arabia over the weekend.

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A trader works on the floor of the New York Stock Exchange.
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A trader works on the floor of the New York Stock Exchange.

The Chicago Fed National Activity Index is due at 08:30 a.m. ET, followed by existing home sales data at 10.00 a.m. ET.

Looking ahead, the third estimate of fourth-quarter 2014 GDP is due Friday, with a slight upwards revision expected, while February's durable goods orders figures will be released on Wednesday.

There are no significant earnings scheduled for Monday.

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Dovish comments from the Federal Reserve helped weaken the dollar last week, as expectations of a rate rise were pushed back.

On Monday, the euro/dollar was up around 0.6 percent at $1.088.

St. Louis Federal Reserve President James Bullard said the strength in the U.S. dollar over recent months had mainly been due to the aggressive policies of the European Central Bank (ECB), rather than the Fed's potential move on rates.

"(The dollar strength) really is the ECB," he told CNBC Monday. "They've resisted this for years."

Bullard also warned that global markets were facing a "mismatch" with the future of U.S. monetary policy and had the potential for major volatility.

Oil prices slipped on Monday after Saudi Arabia said it would not unilaterally cut its output to defend prices over the weekend.

Brent crude oil futures fell around 0.42 percent to trade at $55 a barrel in early London trading, while U.S. WTI crude was down 0.60 percent near $46 a barrel.

Biogen—Stifel downgraded the stock to "hold," stating that the pharmaceutical company has reached a reasonable price target for the next 12 months.

Staples—UBS upgraded the stock to "buy," noting a favorable risk and reward proposition. The investment bank thinks the office supplies retailer will "more likely than not" be able to close its acquisition of Office Depot.

Pfizer—Jefferies added the pharmaceutical company to its "Franchise Picks" list, noting it expects the firm to show significant appreciation over the next one to two years based on better-than-expected launch of breast cancer drug Ibrance. The investment bank also saw potential for more merger and acquisition activity.

Cliffs Natural Resources announced it will sell Chromite assets in Canada to a local mining company, Noront Resources, for $20 million.

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Tenet Healthcare and United Surgical Partners International (USPI) will combine to create the largest provider of ambulatory surgery in the United States in a cash and debt transaction valued at $1.93 billion.