BNP Paribas is reeling from losses at one of its most famed business.

Bloomberg News reports that the bank reported a 70% plunge in revenue at its equities unit in the fourth quarter, the worst performance since at least 2013 and a stark contrast with gains at its biggest U.S. rivals. The slump came after a chaotic December, during which BNP traders were flummoxed by sharp market moves and a series of U.S. trades that went awry around Christmas and lost tens of millions of dollars.

“The guy in charge of the book made bad choices,” COO Philippe Bordenave said, without identifying the individual behind the U.S. derivatives trades. “There is no negligence, no misbehavior at all.”

In the meantime, Bloomberg also reports that just as the staff at ING Groep’s new, centralized, London trading floor were getting to know each other, some may be packing their bags again thanks to Brexit.

The Amsterdam-based bank may relocate dozens of its London positions back to the European continent as the U.K. moves closer to the March 29 Brexit deadline without a deal in place.

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