European shares slid and Spanish and Italian bond yields rose as the political deadlock threatened to reignite the euro zone debt crisis. Greek banking stocks tumbled 7 percent.
Greece's political landscape has been in disarray since an inconclusive election on May 6 left parliament divided between supporters and opponents of a 130 billion euro ($168.3 billion) EU/IMF bailout, with neither side able to form a government.
After Sunday's effort at cajoling party leaders into a coalition proved fruitless, President Karolos Papoulias summoned four party leaders for a fresh round of talks on Monday evening.
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