Car sales fell to their lowest level since 1991 last month, prompting a fresh call by the industry for government intervention to help coax consumers back into deserted showrooms.

The 23 per cent slide attested to the depth of the downturn affecting carmakers, which are now clamouring for state aid on both sides of the Atlantic. It was also the sixth monthly drop running and the steepest so far this year, according to the Society of Motor Manufacturers and Traders.