But BMW still says its UK subsidiary has turned a corner, pointing to the fact that Rover's share of the UK market grew in September to 5.8% from 3.4%.

"The market oriented measures introduced are starting to bite," BMW said.

Rover's decline contrasts with a 10% jump in BMW brand car deliveries to 588,154 units. Sales have been particularly strong in the US, BMW said.

Turning the corner?

On Tuesday, BMW said the launch of the 25 and 45 models would cement a turnaround that started with the launch of the Rover 75 earlier this year.

Figures to date show little evidence of a turnaround. Rover delivered 176,528 cars in the nine months to 30 September, against 253,810 cars in the same period last year. Land Rover sales jumped by about 20%, with the company delivering 133,423 cars, against 111,761 cars before.

About 10,000 Rover 75s were sold in September, of which 4,500 were in the UK.

Overall, BMW group sales advanced 4.8% to 24.7bn euros ($22bn) in the first nine months of 1999, while unit sales dropped 1.2% to 895, 932.

The BBC's Tom Heap: " Business people have been reluctant to choose Rover"

The 25 and 45 models, to be launched on Tuesday at the London motor show, are revised versions of the 200 and 400 small and medium-sized car range.

The 25 and 45 are seen as Rover's only chance to regain ground until a new set of small and medium-sized cars comes on stream in 2002 as part of a �1.7bn project.

Earlier reports suggested that BMW could sell some of Rover's non-core assets. These include pressing and tooling plants.