US Markets

Wall Street uneasy after Greece deal; Yellen eyed

U.S. stock index futures signaled a mostly lower open on Monday as uncertainty surrounded Greece's deal with its euro zone creditors to extend its bailout.

Greece's left-wing government, led by Prime Minister Alexis Tspiras, was given a lifeline when the Eurogroup of euro zone finance ministers reached a deal to extend the country's bailout by four months. To secure the financial lifeline, however, Greece must presenta list of reform proposals on Monday.

Janet Yellen, Chair of the Federal Reserve.
Getty Images

European stocks performed well, with Germany's DAX hitting a new record high, while the FTSE 100 also neared its all-time peak.

This week is set to be eventful on the data front, with Federal Reserve Chair Janet Yellen's semi-annual testimony to Congress due Tuesday and Wednesday. On Monday, the Chicago Fed's national activity index is due at 08.30 a.m. ET, followed by existing home sales at 10.00 a.m. ET. The Texas Manufacturing Outlook Survey is also due at 10.30 a.m. ET.

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Major earnings on Monday include Agrium, Express Scripts, Oneok and Tenet Healthcare after market close.

In Europe, HSBC addressed its tax evasion allegations at its Swiss operations as it reported lower-than-expected profits for 2014.

"We deeply regret and apologize for conduct and compliance failures," the bank said in a statement. Shares traded over 5 percent lower in London after the results.

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Goldman Sachs downgraded Boeing to "sell" from "neutral," saying the jet maker is the most exposed in the industry to aircraft demand risk.

Apple will spend $1.9 billion to build two new European data centers, one in Ireland, the other in Denmark.

Google won dismissal of a lawsuit that had accused it of forcing Android phone makers to designate Google offerings as the default applications.

In an SEC filing, Goldman Sachs revealed it had received a letter from the U.S. attorney concluding that Goldman had violated federal law in connection with the underwriting and sales of residential mortgage backed securities. Goldman said "reasonably possible" legal costs could be $3 billion more than it currently has reserved.

On Friday, U.S. stocks rallied to close at record highs after the resolution between Greece and the euro zone. The Dow Jones industrial average closed up more than 150 points, its first record close for 2015.

The ended the week at its third record close for the year. The Nasdaq also closed higher, within 50 points of the key 5,000 level.

CNBC's Peter Schacknow contributed to this report.