Richemont has succumbed to the recession as the American consumers who traditionally lap up its luxury brands, such as Cartier and Montblanc, turn their backs on the group .

Sales in the Americas, where the United States accounts for the bulk of purchases, fell by 28 per cent in the final three months of last year as the fallout from the worst housing crisis in 70 years reached the top of the personal wealth pyramid.

Americans are the biggest buyers of Richemont's products — with Cartier their favourite of its brands — and make up about 15 per cent of the group's total sales.

Nevertheless, despite the sales slump, Johann Rupert, the South African billionaire who is chairman of Richemont, is investing in Lehman Brothers' private equity unit, which is spinning out into an independent firm after the collapse of its parent in September last year. Reinet Investments, Mr Rupert's Luxembourg-listed vehicle, will pledge $250 million (£172 million) to the Lehman fund.

Overall, Richemont reported a 12 per cent slump in sales for the last three months of 2008 as demand fell “dramatically” in the worst retail environment that the group has faced in its 20-year life.

“Demand for luxury goods, as in other sectors of the economy, has fallen dramatically,” the company said. “We must assume that there will be no significant recovery in the foreseeable future and plan accordingly to cope with this situation. January is a very quiet month and the first quarter usually is a very quiet quarter and I can't imagine there will be a significant improvement.”

The results mark a significant turnaround from September last year, when Richemont reported that the top end of the market was proving resilient to the financial crisis after sales had risen by 11 per cent in the preceding five months. Sales in Europe fell by 9 per cent, while revenues in Japan dropped by 18 per cent. In the Asia Pacific region, sales fell by 2 per cent.

Richemont's pens division, which includes the Montblanc and Monte-grappa brands, was the worst hit, recording a 17 per cent decline in the fourth quarter. The jewellery brands, which include Cartier and Van Cleef & Arpels, reported a 12 per cent drop over the same period.

The group reported total sales of €1.55 billion (£1.40 billion) for the period, which equates to the third quarter of its financial year.

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