By William Boston

BERLIN--New car sales in the European Union got off to a strong start in January, posting the fastest growth in the month since 2010 on the back of rebounding sales in Spain, Italy, the United Kingdom and France.

New car registrations, a reflection of new car sales, rose 6.7% from a year earlier to 999,157 vehicles, according to the Association of European Automobile Manufacturers. That makes last month the best performing January since 2010, when new car sales grew 12.6%.

Opel, the European unit of General Motors Co., was the fastest growing volume brand last month, with new car sales increasing 15.9% to 62,684 vehicles, helping Opel and its U.K.-based sister brand Vauxhall boost market share to 6.3% in January from 5.8% a year ago.

The strong growth in France was driven by robust sales at Renault, the largest French auto maker. Renault brand sales grew 11.3% to 65,035 cars in January.

Sales of the Volkswagen brand, the biggest volume manufacturer in the EU with 12.9% market share, grew 7.7% in January, followed by Ford Motor Co.'s European unit, which saw sales rise 5.1% to 68,774 vehicles. The Fiat brand posted a 4.7% sales increase in January, followed by a 4% increase in sales of the Peugeot brand.

In the premium car segment, sales of Daimler AG's Mercedes-Benz cars rose 12.8%, outpacing BMW AG, which grew 5.8% and Audi, which saw sales growth slow to 1.6% in the region.

Audi was the largest premium brand in the EU in January, with sales of 53,480 cars, followed by Mercedes sales of 49,883 cars and BMW sales of 49,387.

Write to William Boston at william.boston@wsj.com.