Sales of new BMW cars are plummeting as the company suffers a backlash over high prices and its treatment of Rover – whose sales have soared.

Figures to be released within the next week will show that BMW new car registrations in Britain fell by some 20 per cent last month, bucking a surprise rise in sales across the industry. Rover sold nearly five times as many cars last month as it did in April last year.

The figures, which are expected to prompt sharp price cuts by BMW, emerged as the German company began talks about Rover with the Phoenix consortium led by the former Rover director John Towers. The consortium is believed to be seeking finance from HSBC, which has lent heavily to many of Rover’s suppliers.

The fall in BMW sales, down to about 3,500 from 4,400 last year, follows a successful March, and contrasts with an unexpected sales boost for the rest of the industry. Rover is thought to have sold 19,000 cars last month compared with 4,000 in April 1999, after heavy price-cutting and aggressive advertising.

BMW denies that its fall in sales is related to the Rover issue, although more than 100 orders have been cancelled since the withdrawal was announced. Insiders blame a resistance to discounting.