The news moved markets, with Greek bank stocks tumbling and bond yields rising once again.
As Greece's stock market plunges and borrowing costs soar, analysts warned the country could be facing its "Lehman moment" as it faces bankruptcy.
German economic sentiment slipped in April for the first time since last October, closely-watched numbers from the ZEW institute showed on Tuesday.
ARM Holdings beat first quarter profit expectations thanks to iPhone 6 demand .
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Darren Chervitz, portfolio manager at Jacob Asset Management, says that Marissa Mayer's "honeymoon period" as Yahoo CEO is approaching an end, with consumers expecting more core results from Yahoo.
Talking tech and US earnings, Leigh Drogen, CEO of Estimize, says this quarter will be about mobile monetization, especially for Facebook and Twitter.
Charles Newsome, divisional director at Investec Wealth & Investment, says he believes that Greece will move towards some sort of exit from the euro zone in the long term.