Wolfsburg, Germany - Europe's biggest carmaker Volkswagen AG warned Thursday of a tough year ahead after the group said worldwide sales fell 15 per cent during the first two months of 2009 in the wake of the deepening global auto crisis.

"An extremely difficult year lies ahead of us," said VW chief Martin Winterkorn releasing the German-based carmaker's latest results.

However, a new special bonus payment for Germans trading in old cars for new more environmentally based models helped VW to post sales in Germany that were better than many of its rivals in other parts of the world and in its other key markets.

VW reported its best month in Germany since the economic boom unleashed by the fall of the Berlin Wall almost two decade ago with car deliveries in Europe's biggest car market surging by 20 per cent last month.

However, VW said overall sales were dragged down by a steep drop in business in the group's markets in the United States, Japan and Europe as a whole with the global recession gaining momentum as 2009 commenced.

While Winterkorn said VW was maintaining its 2009 earnings target, he warned that the group's earings would fall short of recent years with total car deliveries likely to drop by 10 per cent.

This followed a record year for the world's third biggest automaker with 2008 operating profit rising by 3 per cent to 6.3 billion euros.

After-tax profit last year jumped 13.7 per cent to 4.7 billion euros (6 billion dollars), while sales revenue grew by 4.5 per cent to 113.8 billion euros, VW said.

Boosting VW's business was a strong performance by the world's leading emerging markets with deliveries to South America, the Asian-Pacific region and China rising by 12.5 per cent to more than a million for the first time.

VW hopes a round of new models and vehicle updates will help it to raise the number of cars it sells from 3.67 million last year to 6.6 million in 2018. Alone last year the VW group launched 52 new models, successors and product enhancements.

"Our aim remains to be the top of the automotive industry," said Winterkorn with Japan's Toyota currently occupying the number one sport followed by the ailing US General Motors Corp.

However, VW decided against setting out concrete business projections for the coming year saying "the business outlook for 2009 remains highly uncertain and entails considerable risks.

"The highly volatile market situation does not currently allow any reliable predictions to be made about the further development of this fiscal year," the company said releasing the results. (dpa)