The Athens stock market has reopened — having been shut for five weeks — and it has promptly plunged by more than 22 percent.

The selloff  is hardly a surprise since bank shares make up 20 percent of the main Athens index, and they’ve been hammered in this crisis. But the sharp fall in share prices also reflects anxiety about the third bailout deal, agreed on in principle by the government and its creditors last month.  

Over the weekend, the ruling Syriza party postponed an internal vote on whether it should accept the deal. If it doesn’t, there could be another snap election and that could mean more uncertainty for investors around the world.  

“Don’t underestimate the power of Greece to rock markets going forward,”says Kathleen Brooks, a currency analyst with Forex.com. 

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