The American downturn amidst the ongoing global credit crunch is beginning to take its toll of Jaguar and Land Rover.

Both have suffered major setbacks in January's US car sales figures. Sales of Jaguar models tumbled 52.2 per cent to 664 vehicles, from 1,390 a year ago.

And that is a further blow for the Big Cat after a terrible 2007 - sales were off two per cent in December to 1,522, while the year saw a 24.2 per cent slump at 15,683. But Land Rover, which performed solidly in 2007 across the Pond, seems to have caught a cold, too.

Land Rover sales slipped 16.7 per cent in January to 2,859 vehicles. That followed a dip of 18.7 per cent during December to 4,887, although over the year they were 3.7 per cent up at 48,550.

Both marques are in the process of being sold to Indian conglomerate Tata, with a deal expected to be completed by March 31. And the latest grim statistics are likely to confirm the views of Dearborn bosses that they were right to take the decision to offload the pair.

Ford's total sales fell 4.1 per cent to 159,914 vehicles in January.

Ford-branded vehicles showed a more modest decline, slipping less than one per cent to 131,074, from 132,006 vehicles a year ago.

That will give the company some hope that its massive restructuring in the States may be beginning to bear fruit.

Overall, company truck sales showed a slight decline, falling one per cent to 109,838 vehicles sold. Total car sales were 10 per cent adrift at 50,076 vehicles.

Jim Farley, Ford's group vice president of marketing, said the company was pleased with the January results in a "challenging economic and competitive environment".

But he said sales aren't likely to recover in the near term.

"It's not going to get any easier - at least for a while," Mr Farley added.

He said recent interest rate cuts from the Federal Reserve and a proposed government economic stimulus package might help the economy later in the year, but Ford wasn't counting on that.

"Our plan is based on restructuring our business to be profitable at lower demand and changed mix while also accelerating the development of new products people want to buy," he said.

It has previously been revealed that Jaguar and Land Rover turned a profit for Ford in the fourth quarter of 2007.

Ford cut its net loss for 2007 by £5.1 billion to £1.4 billion.

The Blue Oval company is breaking up its Premier Automotive Group (PAG) stable of luxury European brands, of which Jaguar and Land Rover are part, as a result of a massive cost-cutting programme that has seen more than a dozen factories closed in North America and nearly 33,000 jobs axed.

PAG reported a full-year pretax profit of £258 million in 2007 compared with a loss of £176 million the previous year.

General Motors saw a surprise 2.6 per cent increase in vehicle sales in January on the back of popular new models.

The rest of the major automakers reported sales declines, including Toyota, now the No. 2 best seller in the United States.

Toyota suffered a 2.3 per cent dip.

Chrysler, controlled by Cerberus Capital Management, said sales fell 12 per cent.

Industry executives and analysts broadly expected US auto sales to decline in January, typically a weak month, but the overall figure was worse than most foresaw.

Higher petrol prices combined with the slumping housing market have raised concerns the US economy could tip into recession this year and cause consumers to delay big-ticket purchases such as new vehicles. That has led many in the auto industry to predict a second straight year of lower sales.

They suggest 2008 sales in the range of 15.5 million vehicles - down from 16.14 million last year, their lowest point since 1998.

January sales ran at about 15.26 million vehicles on an annualised basis, adrift almost eight per cent. New models, hybrids like the Toyota Prius and small cars performed best.