French consumer spending stabilised in December as a fall in outlays on energy offset a jump in car sales, confounding expectations of a slight improvement overall during the key holiday season.

Consumer spending was unchanged last month after rising 0.2 per cent in November, data from the INSEE official statistics office showed. A Reuters poll of 15 economists had an average forecast for an increase 0.2 per cent in December.

Over the whole of the final three months of 2012, consumer spending eased 0.1 per cent from the previous quarter, signalling that the traditional motor of the euro zone's second-biggest economy is likely to have weighed down on gross domestic product in the period.

In rare good news for France's beleaguered carmakers, the December data showed that new car sales surged by 4.6 per cent over the month before new fees for high-polluting cars came into effect at the start of this year.

However, spending on energy dropped 3.5 per cent as mild weather reduced households' heating bills.

With unemployment around 15-year highs, consumer spending was dampened over much of 2012 as households entrenched for tough economic times amid a steady stream of headlines about factory closures and layoffs.

Reuters