Société Générale's new chief executive has promoted one of his key lieutenants to replace him as head of the French bank’s finance department, as the business attempts to draw a line under the rogue trader scandal that cost it billions of euros at the start of the year.

Didier Valet, a former head of banking research at Société Générale, has been named finance director, replacing Frédéric Oudéa, who last month became chief executive of the bank.