Mini lost ground again in the US last month as interruptions in production at BMW's Oxford plant translate into falling sales.
The former Rover factory at Cowley is undergoing a £100 million upgrade ahead of the launch of the second generation version of the iconic car, which BMW revived in 2001.
Sales of Mini have beaten all expectations and the factory revamp - which includes a second bodyshell shop and an improved paint shop - will help raise production volumes to more than 200,000, double the projected level.
But sales began to dip at the start of the year after the plant underwent a longer than usual shutdown over Christmas and new year.
And BMW group chairman Helmut Panke said at the Geneva Motor Show this week that building work will interrupt production again in the summer.
Mini sales fell by 14 per cent to 2,690 in the US in February and were seven per cent over the first two months of the year at 5,634.
Meanwhile at Land Rover, which is enjoying the biggest global sales boom in its history, hopes are rising that a plan to make 1,300 workers redundant because of the transfer of Freelander production to Halewood may now be scaled back.
Land Rover sales in the US have risen by 31 per cent so far this year and the company, part of Ford's Premier Automotive Group, is talking to unions about increasing production at Lode Lane to 116,000 units this year from 106,000 in 2005.
"Clearly, if it reached the point that demand meant production had to be stepped up, we would look at the (redundancy) figures again," a Land Rover spokesman said.
The latest US car sales figures showed that Detroit giants General Motors and Ford lost more ground in their home market to Japanese rivals Toyota and Honda in February.
However, Toyota's American sales rose only by 2.4 per cent - well short of the ten per cent gain analysts were expecting. The gain was only about a quarter of the average increase it has posted over the past six months.
Toyota, already the world's most profitable automotive group, is seem-ingly on course to depose GM as the global leader in terms of sales, although senior executives deny that that is the company's ambition.
Argus Research analyst Kevin Tynan said: "I wouldn't read too much into one month of data for any automaker. What I'm looking for more is the trend. And Toyota shows the continuation of a positive trend, albeit at a slower pace."
GM's overall US sales dropped by 2.5 per cent in February and Ford's US sales, excluding its imported brands such as Jaguar, Land Rover and Volvo, were three per cent off. But sales for Chrysler were three per cent ahead.
