Friends of rogue trader Jerome Kerviel last night blamed his $7 billion losses on unbearable levels of stress brought on by a punishing 30 hour week.

Kerviel was known to start work as early as nine in the morning and still be at his desk at five or even five-thirty, often with just an hour and a half for lunch.

One colleague said: «He was, how you say, une workaholique. I have a family and a mistress so I would leave the office at around 2pm at the latest, if I wasn’t on strike.

«But Jerome was tied to that desk. One day I came back to the office at 3pm because I had forgotten my beret, and there he was, fast asleep on the photocopier.

«At first I assumed he had been out until dawn the night before, but then I remembered he’d been working for almost six hours.»

As the losses mounted, Kerviel tried to conceal his bad trades by covering them with an intense red wine sauce, later switching to delicate pastry horns.

At one point he managed to dispose of dozens of transactions by hiding them inside vol-au-vent cases and staging a fake reception.