The dollar tumbled across the board and hit a seven-week low against the yen Thursday, as the unresolved crisis in the US automotive sector and its looming impact on the wider economy savaged confidence in the greenback.

Against the Japanese yen, the dollar dropped 1.6 per cent to Y91.13, retreating to its weakest level since a 13-year low of Y90.58 on October 24, near the psychologically significant Y90 level.