US car giant General Motors sold half a million new vehicles last month, notching up its strongest December sales figures since 1979.

The company, owner of the Cadillac, Chevrolet, Vauxhall and Opel brands, said it sold 473,663 cars and trucks last month, an increase of 36% on the same period one year earlier.

The increase was partly due to discounts and financing plans aimed at increasing GM's share of the US auto market for the second consecutive year.

John Smith, GM's vice president for north American sales described the figure as "outstanding."

Market worries

However, the firm's sales for 2002 as a whole were down 1% on the year at 4.8 million vehicles.

GM, the world's biggest carmaker, said it was on track to produce 1.4 million vehicles in the first three months of 2003, as previously forecast.

Earlier on Friday, GM's arch-rival Ford said its December sales figures were up 8% on the year, while sales for the year as a whole fell about 8.8% to 3.6 million vehicles.

Worries over the health of the US car market have been growing in recent months amid signs of weaker consumer spending and surging oil prices.

The sales figures from the two car giants come ahead of next week's Detroit Motor Show, the world's biggest automotive industry get-together.