Hiroto Saikawa, chief executive, blamed the US slide on a previous policy of pushing sales at all costs: "We are trying to enhance the brand value; that is a big piece of homework we are addressing." The whole industry has struggled against a global slowdown in car sales in the past year as economic uncertainty and a backlash against diesel engines take their toll. But Nissan is also scrambling to maintain its reputation after Mr Ghosn was arrested following allegations he concealed his true income from the Japanese authorities, which he has denied. Mr Saikawa said Nissan bosses were "shocked" by the affair and apologised for having failed to spot the alleged misconduct sooner.