European banks' stocks are taking a beating, and many are chasing lows not seen since February when their shares were hard-hit by plummeting oil prices.
But this time it's for a different reason: the growing likelihood of a Brexit.
The banks are facing the prospect of greater turbulence in the immediate future should Britons vote next week in favor of quitting the European Union, and it is looking more and more like the U.K. is leaning toward "leave."
"Brexit is probably more concerning for EU banks than failing stress tests," said Christopher Whalen, senior managing director at the Kroll Bond Rating Agency. "It's a big unknown. It's certainly not helping large-bank equity valuations."